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Diffstat (limited to 'vendor/gopkg.in/yaml.v2/scannerc.go')
| -rw-r--r-- | vendor/gopkg.in/yaml.v2/scannerc.go | 2710 |
1 files changed, 2710 insertions, 0 deletions
diff --git a/vendor/gopkg.in/yaml.v2/scannerc.go b/vendor/gopkg.in/yaml.v2/scannerc.go new file mode 100644 index 000000000..2c9d5111f --- /dev/null +++ b/vendor/gopkg.in/yaml.v2/scannerc.go @@ -0,0 +1,2710 @@ +package yaml + +import ( + "bytes" + "fmt" +) + +// Introduction +// ************ +// +// The following notes assume that you are familiar with the YAML specification +// (http://yaml.org/spec/1.2/spec.html). We mostly follow it, although in +// some cases we are less restrictive that it requires. +// +// The process of transforming a YAML stream into a sequence of events is +// divided on two steps: Scanning and Parsing. +// +// The Scanner transforms the input stream into a sequence of tokens, while the +// parser transform the sequence of tokens produced by the Scanner into a +// sequence of parsing events. +// +// The Scanner is rather clever and complicated. The Parser, on the contrary, +// is a straightforward implementation of a recursive-descendant parser (or, +// LL(1) parser, as it is usually called). +// +// Actually there are two issues of Scanning that might be called "clever", the +// rest is quite straightforward. The issues are "block collection start" and +// "simple keys". Both issues are explained below in details. +// +// Here the Scanning step is explained and implemented. We start with the list +// of all the tokens produced by the Scanner together with short descriptions. +// +// Now, tokens: +// +// STREAM-START(encoding) # The stream start. +// STREAM-END # The stream end. +// VERSION-DIRECTIVE(major,minor) # The '%YAML' directive. +// TAG-DIRECTIVE(handle,prefix) # The '%TAG' directive. +// DOCUMENT-START # '---' +// DOCUMENT-END # '...' +// BLOCK-SEQUENCE-START # Indentation increase denoting a block +// BLOCK-MAPPING-START # sequence or a block mapping. +// BLOCK-END # Indentation decrease. +// FLOW-SEQUENCE-START # '[' +// FLOW-SEQUENCE-END # ']' +// BLOCK-SEQUENCE-START # '{' +// BLOCK-SEQUENCE-END # '}' +// BLOCK-ENTRY # '-' +// FLOW-ENTRY # ',' +// KEY # '?' or nothing (simple keys). +// VALUE # ':' +// ALIAS(anchor) # '*anchor' +// ANCHOR(anchor) # '&anchor' +// TAG(handle,suffix) # '!handle!suffix' +// SCALAR(value,style) # A scalar. +// +// The following two tokens are "virtual" tokens denoting the beginning and the +// end of the stream: +// +// STREAM-START(encoding) +// STREAM-END +// +// We pass the information about the input stream encoding with the +// STREAM-START token. +// +// The next two tokens are responsible for tags: +// +// VERSION-DIRECTIVE(major,minor) +// TAG-DIRECTIVE(handle,prefix) +// +// Example: +// +// %YAML 1.1 +// %TAG ! !foo +// %TAG !yaml! tag:yaml.org,2002: +// --- +// +// The correspoding sequence of tokens: +// +// STREAM-START(utf-8) +// VERSION-DIRECTIVE(1,1) +// TAG-DIRECTIVE("!","!foo") +// TAG-DIRECTIVE("!yaml","tag:yaml.org,2002:") +// DOCUMENT-START +// STREAM-END +// +// Note that the VERSION-DIRECTIVE and TAG-DIRECTIVE tokens occupy a whole +// line. +// +// The document start and end indicators are represented by: +// +// DOCUMENT-START +// DOCUMENT-END +// +// Note that if a YAML stream contains an implicit document (without '---' +// and '...' indicators), no DOCUMENT-START and DOCUMENT-END tokens will be +// produced. +// +// In the following examples, we present whole documents together with the +// produced tokens. +// +// 1. An implicit document: +// +// 'a scalar' +// +// Tokens: +// +// STREAM-START(utf-8) +// SCALAR("a scalar",single-quoted) +// STREAM-END +// +// 2. An explicit document: +// +// --- +// 'a scalar' +// ... +// +// Tokens: +// +// STREAM-START(utf-8) +// DOCUMENT-START +// SCALAR("a scalar",single-quoted) +// DOCUMENT-END +// STREAM-END +// +// 3. Several documents in a stream: +// +// 'a scalar' +// --- +// 'another scalar' +// --- +// 'yet another scalar' +// +// Tokens: +// +// STREAM-START(utf-8) +// SCALAR("a scalar",single-quoted) +// DOCUMENT-START +// SCALAR("another scalar",single-quoted) +// DOCUMENT-START +// SCALAR("yet another scalar",single-quoted) +// STREAM-END +// +// We have already introduced the SCALAR token above. The following tokens are +// used to describe aliases, anchors, tag, and scalars: +// +// ALIAS(anchor) +// ANCHOR(anchor) +// TAG(handle,suffix) +// SCALAR(value,style) +// +// The following series of examples illustrate the usage of these tokens: +// +// 1. A recursive sequence: +// +// &A [ *A ] +// +// Tokens: +// +// STREAM-START(utf-8) +// ANCHOR("A") +// FLOW-SEQUENCE-START +// ALIAS("A") +// FLOW-SEQUENCE-END +// STREAM-END +// +// 2. A tagged scalar: +// +// !!float "3.14" # A good approximation. +// +// Tokens: +// +// STREAM-START(utf-8) +// TAG("!!","float") +// SCALAR("3.14",double-quoted) +// STREAM-END +// +// 3. Various scalar styles: +// +// --- # Implicit empty plain scalars do not produce tokens. +// --- a plain scalar +// --- 'a single-quoted scalar' +// --- "a double-quoted scalar" +// --- |- +// a literal scalar +// --- >- +// a folded +// scalar +// +// Tokens: +// +// STREAM-START(utf-8) +// DOCUMENT-START +// DOCUMENT-START +// SCALAR("a plain scalar",plain) +// DOCUMENT-START +// SCALAR("a single-quoted scalar",single-quoted) +// DOCUMENT-START +// SCALAR("a double-quoted scalar",double-quoted) +// DOCUMENT-START +// SCALAR("a literal scalar",literal) +// DOCUMENT-START +// SCALAR("a folded scalar",folded) +// STREAM-END +// +// Now it's time to review collection-related tokens. We will start with +// flow collections: +// +// FLOW-SEQUENCE-START +// FLOW-SEQUENCE-END +// FLOW-MAPPING-START +// FLOW-MAPPING-END +// FLOW-ENTRY +// KEY +// VALUE +// +// The tokens FLOW-SEQUENCE-START, FLOW-SEQUENCE-END, FLOW-MAPPING-START, and +// FLOW-MAPPING-END represent the indicators '[', ']', '{', and '}' +// correspondingly. FLOW-ENTRY represent the ',' indicator. Finally the +// indicators '?' and ':', which are used for denoting mapping keys and values, +// are represented by the KEY and VALUE tokens. +// +// The following examples show flow collections: +// +// 1. A flow sequence: +// +// [item 1, item 2, item 3] +// +// Tokens: +// +// STREAM-START(utf-8) +// FLOW-SEQUENCE-START +// SCALAR("item 1",plain) +// FLOW-ENTRY +// SCALAR("item 2",plain) +// FLOW-ENTRY +// SCALAR("item 3",plain) +// FLOW-SEQUENCE-END +// STREAM-END +// +// 2. A flow mapping: +// +// { +// a simple key: a value, # Note that the KEY token is produced. +// ? a complex key: another value, +// } +// +// Tokens: +// +// STREAM-START(utf-8) +// FLOW-MAPPING-START +// KEY +// SCALAR("a simple key",plain) +// VALUE +// SCALAR("a value",plain) +// FLOW-ENTRY +// KEY +// SCALAR("a complex key",plain) +// VALUE +// SCALAR("another value",plain) +// FLOW-ENTRY +// FLOW-MAPPING-END +// STREAM-END +// +// A simple key is a key which is not denoted by the '?' indicator. Note that +// the Scanner still produce the KEY token whenever it encounters a simple key. +// +// For scanning block collections, the following tokens are used (note that we +// repeat KEY and VALUE here): +// +// BLOCK-SEQUENCE-START +// BLOCK-MAPPING-START +// BLOCK-END +// BLOCK-ENTRY +// KEY +// VALUE +// +// The tokens BLOCK-SEQUENCE-START and BLOCK-MAPPING-START denote indentation +// increase that precedes a block collection (cf. the INDENT token in Python). +// The token BLOCK-END denote indentation decrease that ends a block collection +// (cf. the DEDENT token in Python). However YAML has some syntax pecularities +// that makes detections of these tokens more complex. +// +// The tokens BLOCK-ENTRY, KEY, and VALUE are used to represent the indicators +// '-', '?', and ':' correspondingly. +// +// The following examples show how the tokens BLOCK-SEQUENCE-START, +// BLOCK-MAPPING-START, and BLOCK-END are emitted by the Scanner: +// +// 1. Block sequences: +// +// - item 1 +// - item 2 +// - +// - item 3.1 +// - item 3.2 +// - +// key 1: value 1 +// key 2: value 2 +// +// Tokens: +// +// STREAM-START(utf-8) +// BLOCK-SEQUENCE-START +// BLOCK-ENTRY +// SCALAR("item 1",plain) +// BLOCK-ENTRY +// SCALAR("item 2",plain) +// BLOCK-ENTRY +// BLOCK-SEQUENCE-START +// BLOCK-ENTRY +// SCALAR("item 3.1",plain) +// BLOCK-ENTRY +// SCALAR("item 3.2",plain) +// BLOCK-END +// BLOCK-ENTRY +// BLOCK-MAPPING-START +// KEY +// SCALAR("key 1",plain) +// VALUE +// SCALAR("value 1",plain) +// KEY +// SCALAR("key 2",plain) +// VALUE +// SCALAR("value 2",plain) +// BLOCK-END +// BLOCK-END +// STREAM-END +// +// 2. Block mappings: +// +// a simple key: a value # The KEY token is produced here. +// ? a complex key +// : another value +// a mapping: +// key 1: value 1 +// key 2: value 2 +// a sequence: +// - item 1 +// - item 2 +// +// Tokens: +// +// STREAM-START(utf-8) +// BLOCK-MAPPING-START +// KEY +// SCALAR("a simple key",plain) +// VALUE +// SCALAR("a value",plain) +// KEY +// SCALAR("a complex key",plain) +// VALUE +// SCALAR("another value",plain) +// KEY +// SCALAR("a mapping",plain) +// BLOCK-MAPPING-START +// KEY +// SCALAR("key 1",plain) +// VALUE +// SCALAR("value 1",plain) +// KEY +// SCALAR("key 2",plain) +// VALUE +// SCALAR("value 2",plain) +// BLOCK-END +// KEY +// SCALAR("a sequence",plain) +// VALUE +// BLOCK-SEQUENCE-START +// BLOCK-ENTRY +// SCALAR("item 1",plain) +// BLOCK-ENTRY +// SCALAR("item 2",plain) +// BLOCK-END +// BLOCK-END +// STREAM-END +// +// YAML does not always require to start a new block collection from a new +// line. If the current line contains only '-', '?', and ':' indicators, a new +// block collection may start at the current line. The following examples +// illustrate this case: +// +// 1. Collections in a sequence: +// +// - - item 1 +// - item 2 +// - key 1: value 1 +// key 2: value 2 +// - ? complex key +// : complex value +// +// Tokens: +// +// STREAM-START(utf-8) +// BLOCK-SEQUENCE-START +// BLOCK-ENTRY +// BLOCK-SEQUENCE-START +// BLOCK-ENTRY +// SCALAR("item 1",plain) +// BLOCK-ENTRY +// SCALAR("item 2",plain) +// BLOCK-END +// BLOCK-ENTRY +// BLOCK-MAPPING-START +// KEY +// SCALAR("key 1",plain) +// VALUE +// SCALAR("value 1",plain) +// KEY +// SCALAR("key 2",plain) +// VALUE +// SCALAR("value 2",plain) +// BLOCK-END +// BLOCK-ENTRY +// BLOCK-MAPPING-START +// KEY +// SCALAR("complex key") +// VALUE +// SCALAR("complex value") +// BLOCK-END +// BLOCK-END +// STREAM-END +// +// 2. Collections in a mapping: +// +// ? a sequence +// : - item 1 +// - item 2 +// ? a mapping +// : key 1: value 1 +// key 2: value 2 +// +// Tokens: +// +// STREAM-START(utf-8) +// BLOCK-MAPPING-START +// KEY +// SCALAR("a sequence",plain) +// VALUE +// BLOCK-SEQUENCE-START +// BLOCK-ENTRY +// SCALAR("item 1",plain) +// BLOCK-ENTRY +// SCALAR("item 2",plain) +// BLOCK-END +// KEY +// SCALAR("a mapping",plain) +// VALUE +// BLOCK-MAPPING-START +// KEY +// SCALAR("key 1",plain) +// VALUE +// SCALAR("value 1",plain) +// KEY +// SCALAR("key 2",plain) +// VALUE +// SCALAR("value 2",plain) +// BLOCK-END +// BLOCK-END +// STREAM-END +// +// YAML also permits non-indented sequences if they are included into a block +// mapping. In this case, the token BLOCK-SEQUENCE-START is not produced: +// +// key: +// - item 1 # BLOCK-SEQUENCE-START is NOT produced here. +// - item 2 +// +// Tokens: +// +// STREAM-START(utf-8) +// BLOCK-MAPPING-START +// KEY +// SCALAR("key",plain) +// VALUE +// BLOCK-ENTRY +// SCALAR("item 1",plain) +// BLOCK-ENTRY +// SCALAR("item 2",plain) +// BLOCK-END +// + +// Ensure that the buffer contains the required number of characters. +// Return true on success, false on failure (reader error or memory error). +func cache(parser *yaml_parser_t, length int) bool { + // [Go] This was inlined: !cache(A, B) -> unread < B && !update(A, B) + return parser.unread >= length || yaml_parser_update_buffer(parser, length) +} + +// Advance the buffer pointer. +func skip(parser *yaml_parser_t) { + parser.mark.index++ + parser.mark.column++ + parser.unread-- + parser.buffer_pos += width(parser.buffer[parser.buffer_pos]) +} + +func skip_line(parser *yaml_parser_t) { + if is_crlf(parser.buffer, parser.buffer_pos) { + parser.mark.index += 2 + parser.mark.column = 0 + parser.mark.line++ + parser.unread -= 2 + parser.buffer_pos += 2 + } else if is_break(parser.buffer, parser.buffer_pos) { + parser.mark.index++ + parser.mark.column = 0 + parser.mark.line++ + parser.unread-- + parser.buffer_pos += width(parser.buffer[parser.buffer_pos]) + } +} + +// Copy a character to a string buffer and advance pointers. +func read(parser *yaml_parser_t, s []byte) []byte { + w := width(parser.buffer[parser.buffer_pos]) + if w == 0 { + panic("invalid character sequence") + } + if len(s) == 0 { + s = make([]byte, 0, 32) + } + if w == 1 && len(s)+w <= cap(s) { + s = s[:len(s)+1] + s[len(s)-1] = parser.buffer[parser.buffer_pos] + parser.buffer_pos++ + } else { + s = append(s, parser.buffer[parser.buffer_pos:parser.buffer_pos+w]...) + parser.buffer_pos += w + } + parser.mark.index++ + parser.mark.column++ + parser.unread-- + return s +} + +// Copy a line break character to a string buffer and advance pointers. +func read_line(parser *yaml_parser_t, s []byte) []byte { + buf := parser.buffer + pos := parser.buffer_pos + switch { + case buf[pos] == '\r' && buf[pos+1] == '\n': + // CR LF . LF + s = append(s, '\n') + parser.buffer_pos += 2 + parser.mark.index++ + parser.unread-- + case buf[pos] == '\r' || buf[pos] == '\n': + // CR|LF . LF + s = append(s, '\n') + parser.buffer_pos += 1 + case buf[pos] == '\xC2' && buf[pos+1] == '\x85': + // NEL . LF + s = append(s, '\n') + parser.buffer_pos += 2 + case buf[pos] == '\xE2' && buf[pos+1] == '\x80' && (buf[pos+2] == '\xA8' || buf[pos+2] == '\xA9'): + // LS|PS . LS|PS + s = append(s, buf[parser.buffer_pos:pos+3]...) + parser.buffer_pos += 3 + default: + return s + } + parser.mark.index++ + parser.mark.column = 0 + parser.mark.line++ + parser.unread-- + return s +} + +// Get the next token. +func yaml_parser_scan(parser *yaml_parser_t, token *yaml_token_t) bool { + // Erase the token object. + *token = yaml_token_t{} // [Go] Is this necessary? + + // No tokens after STREAM-END or error. + if parser.stream_end_produced || parser.error != yaml_NO_ERROR { + return true + } + + // Ensure that the tokens queue contains enough tokens. + if !parser.token_available { + if !yaml_parser_fetch_more_tokens(parser) { + return false + } + } + + // Fetch the next token from the queue. + *token = parser.tokens[parser.tokens_head] + parser.tokens_head++ + parser.tokens_parsed++ + parser.token_available = false + + if token.typ == yaml_STREAM_END_TOKEN { + parser.stream_end_produced = true + } + return true +} + +// Set the scanner error and return false. +func yaml_parser_set_scanner_error(parser *yaml_parser_t, context string, context_mark yaml_mark_t, problem string) bool { + parser.error = yaml_SCANNER_ERROR + parser.context = context + parser.context_mark = context_mark + parser.problem = problem + parser.problem_mark = parser.mark + return false +} + +func yaml_parser_set_scanner_tag_error(parser *yaml_parser_t, directive bool, context_mark yaml_mark_t, problem string) bool { + context := "while parsing a tag" + if directive { + context = "while parsing a %TAG directive" + } + return yaml_parser_set_scanner_error(parser, context, context_mark, "did not find URI escaped octet") +} + +func trace(args ...interface{}) func() { + pargs := append([]interface{}{"+++"}, args...) + fmt.Println(pargs...) + pargs = append([]interface{}{"---"}, args...) + return func() { fmt.Println(pargs...) } +} + +// Ensure that the tokens queue contains at least one token which can be +// returned to the Parser. +func yaml_parser_fetch_more_tokens(parser *yaml_parser_t) bool { + // While we need more tokens to fetch, do it. + for { + // Check if we really need to fetch more tokens. + need_more_tokens := false + + if parser.tokens_head == len(parser.tokens) { + // Queue is empty. + need_more_tokens = true + } else { + // Check if any potential simple key may occupy the head position. + if !yaml_parser_stale_simple_keys(parser) { + return false + } + + for i := range parser.simple_keys { + simple_key := &parser.simple_keys[i] + if simple_key.possible && simple_key.token_number == parser.tokens_parsed { + need_more_tokens = true + break + } + } + } + + // We are finished. + if !need_more_tokens { + break + } + // Fetch the next token. + if !yaml_parser_fetch_next_token(parser) { + return false + } + } + + parser.token_available = true + return true +} + +// The dispatcher for token fetchers. +func yaml_parser_fetch_next_token(parser *yaml_parser_t) bool { + // Ensure that the buffer is initialized. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + // Check if we just started scanning. Fetch STREAM-START then. + if !parser.stream_start_produced { + return yaml_parser_fetch_stream_start(parser) + } + + // Eat whitespaces and comments until we reach the next token. + if !yaml_parser_scan_to_next_token(parser) { + return false + } + + // Remove obsolete potential simple keys. + if !yaml_parser_stale_simple_keys(parser) { + return false + } + + // Check the indentation level against the current column. + if !yaml_parser_unroll_indent(parser, parser.mark.column) { + return false + } + + // Ensure that the buffer contains at least 4 characters. 4 is the length + // of the longest indicators ('--- ' and '... '). + if parser.unread < 4 && !yaml_parser_update_buffer(parser, 4) { + return false + } + + // Is it the end of the stream? + if is_z(parser.buffer, parser.buffer_pos) { + return yaml_parser_fetch_stream_end(parser) + } + + // Is it a directive? + if parser.mark.column == 0 && parser.buffer[parser.buffer_pos] == '%' { + return yaml_parser_fetch_directive(parser) + } + + buf := parser.buffer + pos := parser.buffer_pos + + // Is it the document start indicator? + if parser.mark.column == 0 && buf[pos] == '-' && buf[pos+1] == '-' && buf[pos+2] == '-' && is_blankz(buf, pos+3) { + return yaml_parser_fetch_document_indicator(parser, yaml_DOCUMENT_START_TOKEN) + } + + // Is it the document end indicator? + if parser.mark.column == 0 && buf[pos] == '.' && buf[pos+1] == '.' && buf[pos+2] == '.' && is_blankz(buf, pos+3) { + return yaml_parser_fetch_document_indicator(parser, yaml_DOCUMENT_END_TOKEN) + } + + // Is it the flow sequence start indicator? + if buf[pos] == '[' { + return yaml_parser_fetch_flow_collection_start(parser, yaml_FLOW_SEQUENCE_START_TOKEN) + } + + // Is it the flow mapping start indicator? + if parser.buffer[parser.buffer_pos] == '{' { + return yaml_parser_fetch_flow_collection_start(parser, yaml_FLOW_MAPPING_START_TOKEN) + } + + // Is it the flow sequence end indicator? + if parser.buffer[parser.buffer_pos] == ']' { + return yaml_parser_fetch_flow_collection_end(parser, + yaml_FLOW_SEQUENCE_END_TOKEN) + } + + // Is it the flow mapping end indicator? + if parser.buffer[parser.buffer_pos] == '}' { + return yaml_parser_fetch_flow_collection_end(parser, + yaml_FLOW_MAPPING_END_TOKEN) + } + + // Is it the flow entry indicator? + if parser.buffer[parser.buffer_pos] == ',' { + return yaml_parser_fetch_flow_entry(parser) + } + + // Is it the block entry indicator? + if parser.buffer[parser.buffer_pos] == '-' && is_blankz(parser.buffer, parser.buffer_pos+1) { + return yaml_parser_fetch_block_entry(parser) + } + + // Is it the key indicator? + if parser.buffer[parser.buffer_pos] == '?' && (parser.flow_level > 0 || is_blankz(parser.buffer, parser.buffer_pos+1)) { + return yaml_parser_fetch_key(parser) + } + + // Is it the value indicator? + if parser.buffer[parser.buffer_pos] == ':' && (parser.flow_level > 0 || is_blankz(parser.buffer, parser.buffer_pos+1)) { + return yaml_parser_fetch_value(parser) + } + + // Is it an alias? + if parser.buffer[parser.buffer_pos] == '*' { + return yaml_parser_fetch_anchor(parser, yaml_ALIAS_TOKEN) + } + + // Is it an anchor? + if parser.buffer[parser.buffer_pos] == '&' { + return yaml_parser_fetch_anchor(parser, yaml_ANCHOR_TOKEN) + } + + // Is it a tag? + if parser.buffer[parser.buffer_pos] == '!' { + return yaml_parser_fetch_tag(parser) + } + + // Is it a literal scalar? + if parser.buffer[parser.buffer_pos] == '|' && parser.flow_level == 0 { + return yaml_parser_fetch_block_scalar(parser, true) + } + + // Is it a folded scalar? + if parser.buffer[parser.buffer_pos] == '>' && parser.flow_level == 0 { + return yaml_parser_fetch_block_scalar(parser, false) + } + + // Is it a single-quoted scalar? + if parser.buffer[parser.buffer_pos] == '\'' { + return yaml_parser_fetch_flow_scalar(parser, true) + } + + // Is it a double-quoted scalar? + if parser.buffer[parser.buffer_pos] == '"' { + return yaml_parser_fetch_flow_scalar(parser, false) + } + + // Is it a plain scalar? + // + // A plain scalar may start with any non-blank characters except + // + // '-', '?', ':', ',', '[', ']', '{', '}', + // '#', '&', '*', '!', '|', '>', '\'', '\"', + // '%', '@', '`'. + // + // In the block context (and, for the '-' indicator, in the flow context + // too), it may also start with the characters + // + // '-', '?', ':' + // + // if it is followed by a non-space character. + // + // The last rule is more restrictive than the specification requires. + // [Go] Make this logic more reasonable. + //switch parser.buffer[parser.buffer_pos] { + //case '-', '?', ':', ',', '?', '-', ',', ':', ']', '[', '}', '{', '&', '#', '!', '*', '>', '|', '"', '\'', '@', '%', '-', '`': + //} + if !(is_blankz(parser.buffer, parser.buffer_pos) || parser.buffer[parser.buffer_pos] == '-' || + parser.buffer[parser.buffer_pos] == '?' || parser.buffer[parser.buffer_pos] == ':' || + parser.buffer[parser.buffer_pos] == ',' || parser.buffer[parser.buffer_pos] == '[' || + parser.buffer[parser.buffer_pos] == ']' || parser.buffer[parser.buffer_pos] == '{' || + parser.buffer[parser.buffer_pos] == '}' || parser.buffer[parser.buffer_pos] == '#' || + parser.buffer[parser.buffer_pos] == '&' || parser.buffer[parser.buffer_pos] == '*' || + parser.buffer[parser.buffer_pos] == '!' || parser.buffer[parser.buffer_pos] == '|' || + parser.buffer[parser.buffer_pos] == '>' || parser.buffer[parser.buffer_pos] == '\'' || + parser.buffer[parser.buffer_pos] == '"' || parser.buffer[parser.buffer_pos] == '%' || + parser.buffer[parser.buffer_pos] == '@' || parser.buffer[parser.buffer_pos] == '`') || + (parser.buffer[parser.buffer_pos] == '-' && !is_blank(parser.buffer, parser.buffer_pos+1)) || + (parser.flow_level == 0 && + (parser.buffer[parser.buffer_pos] == '?' || parser.buffer[parser.buffer_pos] == ':') && + !is_blankz(parser.buffer, parser.buffer_pos+1)) { + return yaml_parser_fetch_plain_scalar(parser) + } + + // If we don't determine the token type so far, it is an error. + return yaml_parser_set_scanner_error(parser, + "while scanning for the next token", parser.mark, + "found character that cannot start any token") +} + +// Check the list of potential simple keys and remove the positions that +// cannot contain simple keys anymore. +func yaml_parser_stale_simple_keys(parser *yaml_parser_t) bool { + // Check for a potential simple key for each flow level. + for i := range parser.simple_keys { + simple_key := &parser.simple_keys[i] + + // The specification requires that a simple key + // + // - is limited to a single line, + // - is shorter than 1024 characters. + if simple_key.possible && (simple_key.mark.line < parser.mark.line || simple_key.mark.index+1024 < parser.mark.index) { + + // Check if the potential simple key to be removed is required. + if simple_key.required { + return yaml_parser_set_scanner_error(parser, + "while scanning a simple key", simple_key.mark, + "could not find expected ':'") + } + simple_key.possible = false + } + } + return true +} + +// Check if a simple key may start at the current position and add it if +// needed. +func yaml_parser_save_simple_key(parser *yaml_parser_t) bool { + // A simple key is required at the current position if the scanner is in + // the block context and the current column coincides with the indentation + // level. + + required := parser.flow_level == 0 && parser.indent == parser.mark.column + + // A simple key is required only when it is the first token in the current + // line. Therefore it is always allowed. But we add a check anyway. + if required && !parser.simple_key_allowed { + panic("should not happen") + } + + // + // If the current position may start a simple key, save it. + // + if parser.simple_key_allowed { + simple_key := yaml_simple_key_t{ + possible: true, + required: required, + token_number: parser.tokens_parsed + (len(parser.tokens) - parser.tokens_head), + } + simple_key.mark = parser.mark + + if !yaml_parser_remove_simple_key(parser) { + return false + } + parser.simple_keys[len(parser.simple_keys)-1] = simple_key + } + return true +} + +// Remove a potential simple key at the current flow level. +func yaml_parser_remove_simple_key(parser *yaml_parser_t) bool { + i := len(parser.simple_keys) - 1 + if parser.simple_keys[i].possible { + // If the key is required, it is an error. + if parser.simple_keys[i].required { + return yaml_parser_set_scanner_error(parser, + "while scanning a simple key", parser.simple_keys[i].mark, + "could not find expected ':'") + } + } + // Remove the key from the stack. + parser.simple_keys[i].possible = false + return true +} + +// Increase the flow level and resize the simple key list if needed. +func yaml_parser_increase_flow_level(parser *yaml_parser_t) bool { + // Reset the simple key on the next level. + parser.simple_keys = append(parser.simple_keys, yaml_simple_key_t{}) + + // Increase the flow level. + parser.flow_level++ + return true +} + +// Decrease the flow level. +func yaml_parser_decrease_flow_level(parser *yaml_parser_t) bool { + if parser.flow_level > 0 { + parser.flow_level-- + parser.simple_keys = parser.simple_keys[:len(parser.simple_keys)-1] + } + return true +} + +// Push the current indentation level to the stack and set the new level +// the current column is greater than the indentation level. In this case, +// append or insert the specified token into the token queue. +func yaml_parser_roll_indent(parser *yaml_parser_t, column, number int, typ yaml_token_type_t, mark yaml_mark_t) bool { + // In the flow context, do nothing. + if parser.flow_level > 0 { + return true + } + + if parser.indent < column { + // Push the current indentation level to the stack and set the new + // indentation level. + parser.indents = append(parser.indents, parser.indent) + parser.indent = column + + // Create a token and insert it into the queue. + token := yaml_token_t{ + typ: typ, + start_mark: mark, + end_mark: mark, + } + if number > -1 { + number -= parser.tokens_parsed + } + yaml_insert_token(parser, number, &token) + } + return true +} + +// Pop indentation levels from the indents stack until the current level +// becomes less or equal to the column. For each indentation level, append +// the BLOCK-END token. +func yaml_parser_unroll_indent(parser *yaml_parser_t, column int) bool { + // In the flow context, do nothing. + if parser.flow_level > 0 { + return true + } + + // Loop through the indentation levels in the stack. + for parser.indent > column { + // Create a token and append it to the queue. + token := yaml_token_t{ + typ: yaml_BLOCK_END_TOKEN, + start_mark: parser.mark, + end_mark: parser.mark, + } + yaml_insert_token(parser, -1, &token) + + // Pop the indentation level. + parser.indent = parser.indents[len(parser.indents)-1] + parser.indents = parser.indents[:len(parser.indents)-1] + } + return true +} + +// Initialize the scanner and produce the STREAM-START token. +func yaml_parser_fetch_stream_start(parser *yaml_parser_t) bool { + + // Set the initial indentation. + parser.indent = -1 + + // Initialize the simple key stack. + parser.simple_keys = append(parser.simple_keys, yaml_simple_key_t{}) + + // A simple key is allowed at the beginning of the stream. + parser.simple_key_allowed = true + + // We have started. + parser.stream_start_produced = true + + // Create the STREAM-START token and append it to the queue. + token := yaml_token_t{ + typ: yaml_STREAM_START_TOKEN, + start_mark: parser.mark, + end_mark: parser.mark, + encoding: parser.encoding, + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the STREAM-END token and shut down the scanner. +func yaml_parser_fetch_stream_end(parser *yaml_parser_t) bool { + + // Force new line. + if parser.mark.column != 0 { + parser.mark.column = 0 + parser.mark.line++ + } + + // Reset the indentation level. + if !yaml_parser_unroll_indent(parser, -1) { + return false + } + + // Reset simple keys. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + parser.simple_key_allowed = false + + // Create the STREAM-END token and append it to the queue. + token := yaml_token_t{ + typ: yaml_STREAM_END_TOKEN, + start_mark: parser.mark, + end_mark: parser.mark, + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce a VERSION-DIRECTIVE or TAG-DIRECTIVE token. +func yaml_parser_fetch_directive(parser *yaml_parser_t) bool { + // Reset the indentation level. + if !yaml_parser_unroll_indent(parser, -1) { + return false + } + + // Reset simple keys. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + parser.simple_key_allowed = false + + // Create the YAML-DIRECTIVE or TAG-DIRECTIVE token. + token := yaml_token_t{} + if !yaml_parser_scan_directive(parser, &token) { + return false + } + // Append the token to the queue. + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the DOCUMENT-START or DOCUMENT-END token. +func yaml_parser_fetch_document_indicator(parser *yaml_parser_t, typ yaml_token_type_t) bool { + // Reset the indentation level. + if !yaml_parser_unroll_indent(parser, -1) { + return false + } + + // Reset simple keys. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + parser.simple_key_allowed = false + + // Consume the token. + start_mark := parser.mark + + skip(parser) + skip(parser) + skip(parser) + + end_mark := parser.mark + + // Create the DOCUMENT-START or DOCUMENT-END token. + token := yaml_token_t{ + typ: typ, + start_mark: start_mark, + end_mark: end_mark, + } + // Append the token to the queue. + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the FLOW-SEQUENCE-START or FLOW-MAPPING-START token. +func yaml_parser_fetch_flow_collection_start(parser *yaml_parser_t, typ yaml_token_type_t) bool { + // The indicators '[' and '{' may start a simple key. + if !yaml_parser_save_simple_key(parser) { + return false + } + + // Increase the flow level. + if !yaml_parser_increase_flow_level(parser) { + return false + } + + // A simple key may follow the indicators '[' and '{'. + parser.simple_key_allowed = true + + // Consume the token. + start_mark := parser.mark + skip(parser) + end_mark := parser.mark + + // Create the FLOW-SEQUENCE-START of FLOW-MAPPING-START token. + token := yaml_token_t{ + typ: typ, + start_mark: start_mark, + end_mark: end_mark, + } + // Append the token to the queue. + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the FLOW-SEQUENCE-END or FLOW-MAPPING-END token. +func yaml_parser_fetch_flow_collection_end(parser *yaml_parser_t, typ yaml_token_type_t) bool { + // Reset any potential simple key on the current flow level. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + // Decrease the flow level. + if !yaml_parser_decrease_flow_level(parser) { + return false + } + + // No simple keys after the indicators ']' and '}'. + parser.simple_key_allowed = false + + // Consume the token. + + start_mark := parser.mark + skip(parser) + end_mark := parser.mark + + // Create the FLOW-SEQUENCE-END of FLOW-MAPPING-END token. + token := yaml_token_t{ + typ: typ, + start_mark: start_mark, + end_mark: end_mark, + } + // Append the token to the queue. + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the FLOW-ENTRY token. +func yaml_parser_fetch_flow_entry(parser *yaml_parser_t) bool { + // Reset any potential simple keys on the current flow level. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + // Simple keys are allowed after ','. + parser.simple_key_allowed = true + + // Consume the token. + start_mark := parser.mark + skip(parser) + end_mark := parser.mark + + // Create the FLOW-ENTRY token and append it to the queue. + token := yaml_token_t{ + typ: yaml_FLOW_ENTRY_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the BLOCK-ENTRY token. +func yaml_parser_fetch_block_entry(parser *yaml_parser_t) bool { + // Check if the scanner is in the block context. + if parser.flow_level == 0 { + // Check if we are allowed to start a new entry. + if !parser.simple_key_allowed { + return yaml_parser_set_scanner_error(parser, "", parser.mark, + "block sequence entries are not allowed in this context") + } + // Add the BLOCK-SEQUENCE-START token if needed. + if !yaml_parser_roll_indent(parser, parser.mark.column, -1, yaml_BLOCK_SEQUENCE_START_TOKEN, parser.mark) { + return false + } + } else { + // It is an error for the '-' indicator to occur in the flow context, + // but we let the Parser detect and report about it because the Parser + // is able to point to the context. + } + + // Reset any potential simple keys on the current flow level. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + // Simple keys are allowed after '-'. + parser.simple_key_allowed = true + + // Consume the token. + start_mark := parser.mark + skip(parser) + end_mark := parser.mark + + // Create the BLOCK-ENTRY token and append it to the queue. + token := yaml_token_t{ + typ: yaml_BLOCK_ENTRY_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the KEY token. +func yaml_parser_fetch_key(parser *yaml_parser_t) bool { + + // In the block context, additional checks are required. + if parser.flow_level == 0 { + // Check if we are allowed to start a new key (not nessesary simple). + if !parser.simple_key_allowed { + return yaml_parser_set_scanner_error(parser, "", parser.mark, + "mapping keys are not allowed in this context") + } + // Add the BLOCK-MAPPING-START token if needed. + if !yaml_parser_roll_indent(parser, parser.mark.column, -1, yaml_BLOCK_MAPPING_START_TOKEN, parser.mark) { + return false + } + } + + // Reset any potential simple keys on the current flow level. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + // Simple keys are allowed after '?' in the block context. + parser.simple_key_allowed = parser.flow_level == 0 + + // Consume the token. + start_mark := parser.mark + skip(parser) + end_mark := parser.mark + + // Create the KEY token and append it to the queue. + token := yaml_token_t{ + typ: yaml_KEY_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the VALUE token. +func yaml_parser_fetch_value(parser *yaml_parser_t) bool { + + simple_key := &parser.simple_keys[len(parser.simple_keys)-1] + + // Have we found a simple key? + if simple_key.possible { + // Create the KEY token and insert it into the queue. + token := yaml_token_t{ + typ: yaml_KEY_TOKEN, + start_mark: simple_key.mark, + end_mark: simple_key.mark, + } + yaml_insert_token(parser, simple_key.token_number-parser.tokens_parsed, &token) + + // In the block context, we may need to add the BLOCK-MAPPING-START token. + if !yaml_parser_roll_indent(parser, simple_key.mark.column, + simple_key.token_number, + yaml_BLOCK_MAPPING_START_TOKEN, simple_key.mark) { + return false + } + + // Remove the simple key. + simple_key.possible = false + + // A simple key cannot follow another simple key. + parser.simple_key_allowed = false + + } else { + // The ':' indicator follows a complex key. + + // In the block context, extra checks are required. + if parser.flow_level == 0 { + + // Check if we are allowed to start a complex value. + if !parser.simple_key_allowed { + return yaml_parser_set_scanner_error(parser, "", parser.mark, + "mapping values are not allowed in this context") + } + + // Add the BLOCK-MAPPING-START token if needed. + if !yaml_parser_roll_indent(parser, parser.mark.column, -1, yaml_BLOCK_MAPPING_START_TOKEN, parser.mark) { + return false + } + } + + // Simple keys after ':' are allowed in the block context. + parser.simple_key_allowed = parser.flow_level == 0 + } + + // Consume the token. + start_mark := parser.mark + skip(parser) + end_mark := parser.mark + + // Create the VALUE token and append it to the queue. + token := yaml_token_t{ + typ: yaml_VALUE_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the ALIAS or ANCHOR token. +func yaml_parser_fetch_anchor(parser *yaml_parser_t, typ yaml_token_type_t) bool { + // An anchor or an alias could be a simple key. + if !yaml_parser_save_simple_key(parser) { + return false + } + + // A simple key cannot follow an anchor or an alias. + parser.simple_key_allowed = false + + // Create the ALIAS or ANCHOR token and append it to the queue. + var token yaml_token_t + if !yaml_parser_scan_anchor(parser, &token, typ) { + return false + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the TAG token. +func yaml_parser_fetch_tag(parser *yaml_parser_t) bool { + // A tag could be a simple key. + if !yaml_parser_save_simple_key(parser) { + return false + } + + // A simple key cannot follow a tag. + parser.simple_key_allowed = false + + // Create the TAG token and append it to the queue. + var token yaml_token_t + if !yaml_parser_scan_tag(parser, &token) { + return false + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the SCALAR(...,literal) or SCALAR(...,folded) tokens. +func yaml_parser_fetch_block_scalar(parser *yaml_parser_t, literal bool) bool { + // Remove any potential simple keys. + if !yaml_parser_remove_simple_key(parser) { + return false + } + + // A simple key may follow a block scalar. + parser.simple_key_allowed = true + + // Create the SCALAR token and append it to the queue. + var token yaml_token_t + if !yaml_parser_scan_block_scalar(parser, &token, literal) { + return false + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the SCALAR(...,single-quoted) or SCALAR(...,double-quoted) tokens. +func yaml_parser_fetch_flow_scalar(parser *yaml_parser_t, single bool) bool { + // A plain scalar could be a simple key. + if !yaml_parser_save_simple_key(parser) { + return false + } + + // A simple key cannot follow a flow scalar. + parser.simple_key_allowed = false + + // Create the SCALAR token and append it to the queue. + var token yaml_token_t + if !yaml_parser_scan_flow_scalar(parser, &token, single) { + return false + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Produce the SCALAR(...,plain) token. +func yaml_parser_fetch_plain_scalar(parser *yaml_parser_t) bool { + // A plain scalar could be a simple key. + if !yaml_parser_save_simple_key(parser) { + return false + } + + // A simple key cannot follow a flow scalar. + parser.simple_key_allowed = false + + // Create the SCALAR token and append it to the queue. + var token yaml_token_t + if !yaml_parser_scan_plain_scalar(parser, &token) { + return false + } + yaml_insert_token(parser, -1, &token) + return true +} + +// Eat whitespaces and comments until the next token is found. +func yaml_parser_scan_to_next_token(parser *yaml_parser_t) bool { + + // Until the next token is not found. + for { + // Allow the BOM mark to start a line. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + if parser.mark.column == 0 && is_bom(parser.buffer, parser.buffer_pos) { + skip(parser) + } + + // Eat whitespaces. + // Tabs are allowed: + // - in the flow context + // - in the block context, but not at the beginning of the line or + // after '-', '?', or ':' (complex value). + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + for parser.buffer[parser.buffer_pos] == ' ' || ((parser.flow_level > 0 || !parser.simple_key_allowed) && parser.buffer[parser.buffer_pos] == '\t') { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Eat a comment until a line break. + if parser.buffer[parser.buffer_pos] == '#' { + for !is_breakz(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + } + + // If it is a line break, eat it. + if is_break(parser.buffer, parser.buffer_pos) { + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + skip_line(parser) + + // In the block context, a new line may start a simple key. + if parser.flow_level == 0 { + parser.simple_key_allowed = true + } + } else { + break // We have found a token. + } + } + + return true +} + +// Scan a YAML-DIRECTIVE or TAG-DIRECTIVE token. +// +// Scope: +// %YAML 1.1 # a comment \n +// ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +// %TAG !yaml! tag:yaml.org,2002: \n +// ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +// +func yaml_parser_scan_directive(parser *yaml_parser_t, token *yaml_token_t) bool { + // Eat '%'. + start_mark := parser.mark + skip(parser) + + // Scan the directive name. + var name []byte + if !yaml_parser_scan_directive_name(parser, start_mark, &name) { + return false + } + + // Is it a YAML directive? + if bytes.Equal(name, []byte("YAML")) { + // Scan the VERSION directive value. + var major, minor int8 + if !yaml_parser_scan_version_directive_value(parser, start_mark, &major, &minor) { + return false + } + end_mark := parser.mark + + // Create a VERSION-DIRECTIVE token. + *token = yaml_token_t{ + typ: yaml_VERSION_DIRECTIVE_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + major: major, + minor: minor, + } + + // Is it a TAG directive? + } else if bytes.Equal(name, []byte("TAG")) { + // Scan the TAG directive value. + var handle, prefix []byte + if !yaml_parser_scan_tag_directive_value(parser, start_mark, &handle, &prefix) { + return false + } + end_mark := parser.mark + + // Create a TAG-DIRECTIVE token. + *token = yaml_token_t{ + typ: yaml_TAG_DIRECTIVE_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + value: handle, + prefix: prefix, + } + + // Unknown directive. + } else { + yaml_parser_set_scanner_error(parser, "while scanning a directive", + start_mark, "found unknown directive name") + return false + } + + // Eat the rest of the line including any comments. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + for is_blank(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + if parser.buffer[parser.buffer_pos] == '#' { + for !is_breakz(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + } + + // Check if we are at the end of the line. + if !is_breakz(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a directive", + start_mark, "did not find expected comment or line break") + return false + } + + // Eat a line break. + if is_break(parser.buffer, parser.buffer_pos) { + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + skip_line(parser) + } + + return true +} + +// Scan the directive name. +// +// Scope: +// %YAML 1.1 # a comment \n +// ^^^^ +// %TAG !yaml! tag:yaml.org,2002: \n +// ^^^ +// +func yaml_parser_scan_directive_name(parser *yaml_parser_t, start_mark yaml_mark_t, name *[]byte) bool { + // Consume the directive name. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + var s []byte + for is_alpha(parser.buffer, parser.buffer_pos) { + s = read(parser, s) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Check if the name is empty. + if len(s) == 0 { + yaml_parser_set_scanner_error(parser, "while scanning a directive", + start_mark, "could not find expected directive name") + return false + } + + // Check for an blank character after the name. + if !is_blankz(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a directive", + start_mark, "found unexpected non-alphabetical character") + return false + } + *name = s + return true +} + +// Scan the value of VERSION-DIRECTIVE. +// +// Scope: +// %YAML 1.1 # a comment \n +// ^^^^^^ +func yaml_parser_scan_version_directive_value(parser *yaml_parser_t, start_mark yaml_mark_t, major, minor *int8) bool { + // Eat whitespaces. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + for is_blank(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Consume the major version number. + if !yaml_parser_scan_version_directive_number(parser, start_mark, major) { + return false + } + + // Eat '.'. + if parser.buffer[parser.buffer_pos] != '.' { + return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive", + start_mark, "did not find expected digit or '.' character") + } + + skip(parser) + + // Consume the minor version number. + if !yaml_parser_scan_version_directive_number(parser, start_mark, minor) { + return false + } + return true +} + +const max_number_length = 2 + +// Scan the version number of VERSION-DIRECTIVE. +// +// Scope: +// %YAML 1.1 # a comment \n +// ^ +// %YAML 1.1 # a comment \n +// ^ +func yaml_parser_scan_version_directive_number(parser *yaml_parser_t, start_mark yaml_mark_t, number *int8) bool { + + // Repeat while the next character is digit. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + var value, length int8 + for is_digit(parser.buffer, parser.buffer_pos) { + // Check if the number is too long. + length++ + if length > max_number_length { + return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive", + start_mark, "found extremely long version number") + } + value = value*10 + int8(as_digit(parser.buffer, parser.buffer_pos)) + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Check if the number was present. + if length == 0 { + return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive", + start_mark, "did not find expected version number") + } + *number = value + return true +} + +// Scan the value of a TAG-DIRECTIVE token. +// +// Scope: +// %TAG !yaml! tag:yaml.org,2002: \n +// ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +// +func yaml_parser_scan_tag_directive_value(parser *yaml_parser_t, start_mark yaml_mark_t, handle, prefix *[]byte) bool { + var handle_value, prefix_value []byte + + // Eat whitespaces. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + for is_blank(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Scan a handle. + if !yaml_parser_scan_tag_handle(parser, true, start_mark, &handle_value) { + return false + } + + // Expect a whitespace. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + if !is_blank(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive", + start_mark, "did not find expected whitespace") + return false + } + + // Eat whitespaces. + for is_blank(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Scan a prefix. + if !yaml_parser_scan_tag_uri(parser, true, nil, start_mark, &prefix_value) { + return false + } + + // Expect a whitespace or line break. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + if !is_blankz(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive", + start_mark, "did not find expected whitespace or line break") + return false + } + + *handle = handle_value + *prefix = prefix_value + return true +} + +func yaml_parser_scan_anchor(parser *yaml_parser_t, token *yaml_token_t, typ yaml_token_type_t) bool { + var s []byte + + // Eat the indicator character. + start_mark := parser.mark + skip(parser) + + // Consume the value. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + for is_alpha(parser.buffer, parser.buffer_pos) { + s = read(parser, s) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + end_mark := parser.mark + + /* + * Check if length of the anchor is greater than 0 and it is followed by + * a whitespace character or one of the indicators: + * + * '?', ':', ',', ']', '}', '%', '@', '`'. + */ + + if len(s) == 0 || + !(is_blankz(parser.buffer, parser.buffer_pos) || parser.buffer[parser.buffer_pos] == '?' || + parser.buffer[parser.buffer_pos] == ':' || parser.buffer[parser.buffer_pos] == ',' || + parser.buffer[parser.buffer_pos] == ']' || parser.buffer[parser.buffer_pos] == '}' || + parser.buffer[parser.buffer_pos] == '%' || parser.buffer[parser.buffer_pos] == '@' || + parser.buffer[parser.buffer_pos] == '`') { + context := "while scanning an alias" + if typ == yaml_ANCHOR_TOKEN { + context = "while scanning an anchor" + } + yaml_parser_set_scanner_error(parser, context, start_mark, + "did not find expected alphabetic or numeric character") + return false + } + + // Create a token. + *token = yaml_token_t{ + typ: typ, + start_mark: start_mark, + end_mark: end_mark, + value: s, + } + + return true +} + +/* + * Scan a TAG token. + */ + +func yaml_parser_scan_tag(parser *yaml_parser_t, token *yaml_token_t) bool { + var handle, suffix []byte + + start_mark := parser.mark + + // Check if the tag is in the canonical form. + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + + if parser.buffer[parser.buffer_pos+1] == '<' { + // Keep the handle as '' + + // Eat '!<' + skip(parser) + skip(parser) + + // Consume the tag value. + if !yaml_parser_scan_tag_uri(parser, false, nil, start_mark, &suffix) { + return false + } + + // Check for '>' and eat it. + if parser.buffer[parser.buffer_pos] != '>' { + yaml_parser_set_scanner_error(parser, "while scanning a tag", + start_mark, "did not find the expected '>'") + return false + } + + skip(parser) + } else { + // The tag has either the '!suffix' or the '!handle!suffix' form. + + // First, try to scan a handle. + if !yaml_parser_scan_tag_handle(parser, false, start_mark, &handle) { + return false + } + + // Check if it is, indeed, handle. + if handle[0] == '!' && len(handle) > 1 && handle[len(handle)-1] == '!' { + // Scan the suffix now. + if !yaml_parser_scan_tag_uri(parser, false, nil, start_mark, &suffix) { + return false + } + } else { + // It wasn't a handle after all. Scan the rest of the tag. + if !yaml_parser_scan_tag_uri(parser, false, handle, start_mark, &suffix) { + return false + } + + // Set the handle to '!'. + handle = []byte{'!'} + + // A special case: the '!' tag. Set the handle to '' and the + // suffix to '!'. + if len(suffix) == 0 { + handle, suffix = suffix, handle + } + } + } + + // Check the character which ends the tag. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + if !is_blankz(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a tag", + start_mark, "did not find expected whitespace or line break") + return false + } + + end_mark := parser.mark + + // Create a token. + *token = yaml_token_t{ + typ: yaml_TAG_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + value: handle, + suffix: suffix, + } + return true +} + +// Scan a tag handle. +func yaml_parser_scan_tag_handle(parser *yaml_parser_t, directive bool, start_mark yaml_mark_t, handle *[]byte) bool { + // Check the initial '!' character. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + if parser.buffer[parser.buffer_pos] != '!' { + yaml_parser_set_scanner_tag_error(parser, directive, + start_mark, "did not find expected '!'") + return false + } + + var s []byte + + // Copy the '!' character. + s = read(parser, s) + + // Copy all subsequent alphabetical and numerical characters. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + for is_alpha(parser.buffer, parser.buffer_pos) { + s = read(parser, s) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Check if the trailing character is '!' and copy it. + if parser.buffer[parser.buffer_pos] == '!' { + s = read(parser, s) + } else { + // It's either the '!' tag or not really a tag handle. If it's a %TAG + // directive, it's an error. If it's a tag token, it must be a part of URI. + if directive && !(s[0] == '!' && s[1] == 0) { + yaml_parser_set_scanner_tag_error(parser, directive, + start_mark, "did not find expected '!'") + return false + } + } + + *handle = s + return true +} + +// Scan a tag. +func yaml_parser_scan_tag_uri(parser *yaml_parser_t, directive bool, head []byte, start_mark yaml_mark_t, uri *[]byte) bool { + //size_t length = head ? strlen((char *)head) : 0 + var s []byte + + // Copy the head if needed. + // + // Note that we don't copy the leading '!' character. + if len(head) > 1 { + s = append(s, head[1:]...) + } + + // Scan the tag. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + // The set of characters that may appear in URI is as follows: + // + // '0'-'9', 'A'-'Z', 'a'-'z', '_', '-', ';', '/', '?', ':', '@', '&', + // '=', '+', '$', ',', '.', '!', '~', '*', '\'', '(', ')', '[', ']', + // '%'. + // [Go] Convert this into more reasonable logic. + for is_alpha(parser.buffer, parser.buffer_pos) || parser.buffer[parser.buffer_pos] == ';' || + parser.buffer[parser.buffer_pos] == '/' || parser.buffer[parser.buffer_pos] == '?' || + parser.buffer[parser.buffer_pos] == ':' || parser.buffer[parser.buffer_pos] == '@' || + parser.buffer[parser.buffer_pos] == '&' || parser.buffer[parser.buffer_pos] == '=' || + parser.buffer[parser.buffer_pos] == '+' || parser.buffer[parser.buffer_pos] == '$' || + parser.buffer[parser.buffer_pos] == ',' || parser.buffer[parser.buffer_pos] == '.' || + parser.buffer[parser.buffer_pos] == '!' || parser.buffer[parser.buffer_pos] == '~' || + parser.buffer[parser.buffer_pos] == '*' || parser.buffer[parser.buffer_pos] == '\'' || + parser.buffer[parser.buffer_pos] == '(' || parser.buffer[parser.buffer_pos] == ')' || + parser.buffer[parser.buffer_pos] == '[' || parser.buffer[parser.buffer_pos] == ']' || + parser.buffer[parser.buffer_pos] == '%' { + // Check if it is a URI-escape sequence. + if parser.buffer[parser.buffer_pos] == '%' { + if !yaml_parser_scan_uri_escapes(parser, directive, start_mark, &s) { + return false + } + } else { + s = read(parser, s) + } + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Check if the tag is non-empty. + if len(s) == 0 { + yaml_parser_set_scanner_tag_error(parser, directive, + start_mark, "did not find expected tag URI") + return false + } + *uri = s + return true +} + +// Decode an URI-escape sequence corresponding to a single UTF-8 character. +func yaml_parser_scan_uri_escapes(parser *yaml_parser_t, directive bool, start_mark yaml_mark_t, s *[]byte) bool { + + // Decode the required number of characters. + w := 1024 + for w > 0 { + // Check for a URI-escaped octet. + if parser.unread < 3 && !yaml_parser_update_buffer(parser, 3) { + return false + } + + if !(parser.buffer[parser.buffer_pos] == '%' && + is_hex(parser.buffer, parser.buffer_pos+1) && + is_hex(parser.buffer, parser.buffer_pos+2)) { + return yaml_parser_set_scanner_tag_error(parser, directive, + start_mark, "did not find URI escaped octet") + } + + // Get the octet. + octet := byte((as_hex(parser.buffer, parser.buffer_pos+1) << 4) + as_hex(parser.buffer, parser.buffer_pos+2)) + + // If it is the leading octet, determine the length of the UTF-8 sequence. + if w == 1024 { + w = width(octet) + if w == 0 { + return yaml_parser_set_scanner_tag_error(parser, directive, + start_mark, "found an incorrect leading UTF-8 octet") + } + } else { + // Check if the trailing octet is correct. + if octet&0xC0 != 0x80 { + return yaml_parser_set_scanner_tag_error(parser, directive, + start_mark, "found an incorrect trailing UTF-8 octet") + } + } + + // Copy the octet and move the pointers. + *s = append(*s, octet) + skip(parser) + skip(parser) + skip(parser) + w-- + } + return true +} + +// Scan a block scalar. +func yaml_parser_scan_block_scalar(parser *yaml_parser_t, token *yaml_token_t, literal bool) bool { + // Eat the indicator '|' or '>'. + start_mark := parser.mark + skip(parser) + + // Scan the additional block scalar indicators. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + // Check for a chomping indicator. + var chomping, increment int + if parser.buffer[parser.buffer_pos] == '+' || parser.buffer[parser.buffer_pos] == '-' { + // Set the chomping method and eat the indicator. + if parser.buffer[parser.buffer_pos] == '+' { + chomping = +1 + } else { + chomping = -1 + } + skip(parser) + + // Check for an indentation indicator. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + if is_digit(parser.buffer, parser.buffer_pos) { + // Check that the indentation is greater than 0. + if parser.buffer[parser.buffer_pos] == '0' { + yaml_parser_set_scanner_error(parser, "while scanning a block scalar", + start_mark, "found an indentation indicator equal to 0") + return false + } + + // Get the indentation level and eat the indicator. + increment = as_digit(parser.buffer, parser.buffer_pos) + skip(parser) + } + + } else if is_digit(parser.buffer, parser.buffer_pos) { + // Do the same as above, but in the opposite order. + + if parser.buffer[parser.buffer_pos] == '0' { + yaml_parser_set_scanner_error(parser, "while scanning a block scalar", + start_mark, "found an indentation indicator equal to 0") + return false + } + increment = as_digit(parser.buffer, parser.buffer_pos) + skip(parser) + + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + if parser.buffer[parser.buffer_pos] == '+' || parser.buffer[parser.buffer_pos] == '-' { + if parser.buffer[parser.buffer_pos] == '+' { + chomping = +1 + } else { + chomping = -1 + } + skip(parser) + } + } + + // Eat whitespaces and comments to the end of the line. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + for is_blank(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + if parser.buffer[parser.buffer_pos] == '#' { + for !is_breakz(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + } + + // Check if we are at the end of the line. + if !is_breakz(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a block scalar", + start_mark, "did not find expected comment or line break") + return false + } + + // Eat a line break. + if is_break(parser.buffer, parser.buffer_pos) { + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + skip_line(parser) + } + + end_mark := parser.mark + + // Set the indentation level if it was specified. + var indent int + if increment > 0 { + if parser.indent >= 0 { + indent = parser.indent + increment + } else { + indent = increment + } + } + + // Scan the leading line breaks and determine the indentation level if needed. + var s, leading_break, trailing_breaks []byte + if !yaml_parser_scan_block_scalar_breaks(parser, &indent, &trailing_breaks, start_mark, &end_mark) { + return false + } + + // Scan the block scalar content. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + var leading_blank, trailing_blank bool + for parser.mark.column == indent && !is_z(parser.buffer, parser.buffer_pos) { + // We are at the beginning of a non-empty line. + + // Is it a trailing whitespace? + trailing_blank = is_blank(parser.buffer, parser.buffer_pos) + + // Check if we need to fold the leading line break. + if !literal && !leading_blank && !trailing_blank && len(leading_break) > 0 && leading_break[0] == '\n' { + // Do we need to join the lines by space? + if len(trailing_breaks) == 0 { + s = append(s, ' ') + } + } else { + s = append(s, leading_break...) + } + leading_break = leading_break[:0] + + // Append the remaining line breaks. + s = append(s, trailing_breaks...) + trailing_breaks = trailing_breaks[:0] + + // Is it a leading whitespace? + leading_blank = is_blank(parser.buffer, parser.buffer_pos) + + // Consume the current line. + for !is_breakz(parser.buffer, parser.buffer_pos) { + s = read(parser, s) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Consume the line break. + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + + leading_break = read_line(parser, leading_break) + + // Eat the following indentation spaces and line breaks. + if !yaml_parser_scan_block_scalar_breaks(parser, &indent, &trailing_breaks, start_mark, &end_mark) { + return false + } + } + + // Chomp the tail. + if chomping != -1 { + s = append(s, leading_break...) + } + if chomping == 1 { + s = append(s, trailing_breaks...) + } + + // Create a token. + *token = yaml_token_t{ + typ: yaml_SCALAR_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + value: s, + style: yaml_LITERAL_SCALAR_STYLE, + } + if !literal { + token.style = yaml_FOLDED_SCALAR_STYLE + } + return true +} + +// Scan indentation spaces and line breaks for a block scalar. Determine the +// indentation level if needed. +func yaml_parser_scan_block_scalar_breaks(parser *yaml_parser_t, indent *int, breaks *[]byte, start_mark yaml_mark_t, end_mark *yaml_mark_t) bool { + *end_mark = parser.mark + + // Eat the indentation spaces and line breaks. + max_indent := 0 + for { + // Eat the indentation spaces. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + for (*indent == 0 || parser.mark.column < *indent) && is_space(parser.buffer, parser.buffer_pos) { + skip(parser) + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + if parser.mark.column > max_indent { + max_indent = parser.mark.column + } + + // Check for a tab character messing the indentation. + if (*indent == 0 || parser.mark.column < *indent) && is_tab(parser.buffer, parser.buffer_pos) { + return yaml_parser_set_scanner_error(parser, "while scanning a block scalar", + start_mark, "found a tab character where an indentation space is expected") + } + + // Have we found a non-empty line? + if !is_break(parser.buffer, parser.buffer_pos) { + break + } + + // Consume the line break. + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + // [Go] Should really be returning breaks instead. + *breaks = read_line(parser, *breaks) + *end_mark = parser.mark + } + + // Determine the indentation level if needed. + if *indent == 0 { + *indent = max_indent + if *indent < parser.indent+1 { + *indent = parser.indent + 1 + } + if *indent < 1 { + *indent = 1 + } + } + return true +} + +// Scan a quoted scalar. +func yaml_parser_scan_flow_scalar(parser *yaml_parser_t, token *yaml_token_t, single bool) bool { + // Eat the left quote. + start_mark := parser.mark + skip(parser) + + // Consume the content of the quoted scalar. + var s, leading_break, trailing_breaks, whitespaces []byte + for { + // Check that there are no document indicators at the beginning of the line. + if parser.unread < 4 && !yaml_parser_update_buffer(parser, 4) { + return false + } + + if parser.mark.column == 0 && + ((parser.buffer[parser.buffer_pos+0] == '-' && + parser.buffer[parser.buffer_pos+1] == '-' && + parser.buffer[parser.buffer_pos+2] == '-') || + (parser.buffer[parser.buffer_pos+0] == '.' && + parser.buffer[parser.buffer_pos+1] == '.' && + parser.buffer[parser.buffer_pos+2] == '.')) && + is_blankz(parser.buffer, parser.buffer_pos+3) { + yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar", + start_mark, "found unexpected document indicator") + return false + } + + // Check for EOF. + if is_z(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar", + start_mark, "found unexpected end of stream") + return false + } + + // Consume non-blank characters. + leading_blanks := false + for !is_blankz(parser.buffer, parser.buffer_pos) { + if single && parser.buffer[parser.buffer_pos] == '\'' && parser.buffer[parser.buffer_pos+1] == '\'' { + // Is is an escaped single quote. + s = append(s, '\'') + skip(parser) + skip(parser) + + } else if single && parser.buffer[parser.buffer_pos] == '\'' { + // It is a right single quote. + break + } else if !single && parser.buffer[parser.buffer_pos] == '"' { + // It is a right double quote. + break + + } else if !single && parser.buffer[parser.buffer_pos] == '\\' && is_break(parser.buffer, parser.buffer_pos+1) { + // It is an escaped line break. + if parser.unread < 3 && !yaml_parser_update_buffer(parser, 3) { + return false + } + skip(parser) + skip_line(parser) + leading_blanks = true + break + + } else if !single && parser.buffer[parser.buffer_pos] == '\\' { + // It is an escape sequence. + code_length := 0 + + // Check the escape character. + switch parser.buffer[parser.buffer_pos+1] { + case '0': + s = append(s, 0) + case 'a': + s = append(s, '\x07') + case 'b': + s = append(s, '\x08') + case 't', '\t': + s = append(s, '\x09') + case 'n': + s = append(s, '\x0A') + case 'v': + s = append(s, '\x0B') + case 'f': + s = append(s, '\x0C') + case 'r': + s = append(s, '\x0D') + case 'e': + s = append(s, '\x1B') + case ' ': + s = append(s, '\x20') + case '"': + s = append(s, '"') + case '\'': + s = append(s, '\'') + case '\\': + s = append(s, '\\') + case 'N': // NEL (#x85) + s = append(s, '\xC2') + s = append(s, '\x85') + case '_': // #xA0 + s = append(s, '\xC2') + s = append(s, '\xA0') + case 'L': // LS (#x2028) + s = append(s, '\xE2') + s = append(s, '\x80') + s = append(s, '\xA8') + case 'P': // PS (#x2029) + s = append(s, '\xE2') + s = append(s, '\x80') + s = append(s, '\xA9') + case 'x': + code_length = 2 + case 'u': + code_length = 4 + case 'U': + code_length = 8 + default: + yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar", + start_mark, "found unknown escape character") + return false + } + + skip(parser) + skip(parser) + + // Consume an arbitrary escape code. + if code_length > 0 { + var value int + + // Scan the character value. + if parser.unread < code_length && !yaml_parser_update_buffer(parser, code_length) { + return false + } + for k := 0; k < code_length; k++ { + if !is_hex(parser.buffer, parser.buffer_pos+k) { + yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar", + start_mark, "did not find expected hexdecimal number") + return false + } + value = (value << 4) + as_hex(parser.buffer, parser.buffer_pos+k) + } + + // Check the value and write the character. + if (value >= 0xD800 && value <= 0xDFFF) || value > 0x10FFFF { + yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar", + start_mark, "found invalid Unicode character escape code") + return false + } + if value <= 0x7F { + s = append(s, byte(value)) + } else if value <= 0x7FF { + s = append(s, byte(0xC0+(value>>6))) + s = append(s, byte(0x80+(value&0x3F))) + } else if value <= 0xFFFF { + s = append(s, byte(0xE0+(value>>12))) + s = append(s, byte(0x80+((value>>6)&0x3F))) + s = append(s, byte(0x80+(value&0x3F))) + } else { + s = append(s, byte(0xF0+(value>>18))) + s = append(s, byte(0x80+((value>>12)&0x3F))) + s = append(s, byte(0x80+((value>>6)&0x3F))) + s = append(s, byte(0x80+(value&0x3F))) + } + + // Advance the pointer. + for k := 0; k < code_length; k++ { + skip(parser) + } + } + } else { + // It is a non-escaped non-blank character. + s = read(parser, s) + } + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + } + + // Check if we are at the end of the scalar. + if single { + if parser.buffer[parser.buffer_pos] == '\'' { + break + } + } else { + if parser.buffer[parser.buffer_pos] == '"' { + break + } + } + + // Consume blank characters. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + for is_blank(parser.buffer, parser.buffer_pos) || is_break(parser.buffer, parser.buffer_pos) { + if is_blank(parser.buffer, parser.buffer_pos) { + // Consume a space or a tab character. + if !leading_blanks { + whitespaces = read(parser, whitespaces) + } else { + skip(parser) + } + } else { + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + + // Check if it is a first line break. + if !leading_blanks { + whitespaces = whitespaces[:0] + leading_break = read_line(parser, leading_break) + leading_blanks = true + } else { + trailing_breaks = read_line(parser, trailing_breaks) + } + } + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Join the whitespaces or fold line breaks. + if leading_blanks { + // Do we need to fold line breaks? + if len(leading_break) > 0 && leading_break[0] == '\n' { + if len(trailing_breaks) == 0 { + s = append(s, ' ') + } else { + s = append(s, trailing_breaks...) + } + } else { + s = append(s, leading_break...) + s = append(s, trailing_breaks...) + } + trailing_breaks = trailing_breaks[:0] + leading_break = leading_break[:0] + } else { + s = append(s, whitespaces...) + whitespaces = whitespaces[:0] + } + } + + // Eat the right quote. + skip(parser) + end_mark := parser.mark + + // Create a token. + *token = yaml_token_t{ + typ: yaml_SCALAR_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + value: s, + style: yaml_SINGLE_QUOTED_SCALAR_STYLE, + } + if !single { + token.style = yaml_DOUBLE_QUOTED_SCALAR_STYLE + } + return true +} + +// Scan a plain scalar. +func yaml_parser_scan_plain_scalar(parser *yaml_parser_t, token *yaml_token_t) bool { + + var s, leading_break, trailing_breaks, whitespaces []byte + var leading_blanks bool + var indent = parser.indent + 1 + + start_mark := parser.mark + end_mark := parser.mark + + // Consume the content of the plain scalar. + for { + // Check for a document indicator. + if parser.unread < 4 && !yaml_parser_update_buffer(parser, 4) { + return false + } + if parser.mark.column == 0 && + ((parser.buffer[parser.buffer_pos+0] == '-' && + parser.buffer[parser.buffer_pos+1] == '-' && + parser.buffer[parser.buffer_pos+2] == '-') || + (parser.buffer[parser.buffer_pos+0] == '.' && + parser.buffer[parser.buffer_pos+1] == '.' && + parser.buffer[parser.buffer_pos+2] == '.')) && + is_blankz(parser.buffer, parser.buffer_pos+3) { + break + } + + // Check for a comment. + if parser.buffer[parser.buffer_pos] == '#' { + break + } + + // Consume non-blank characters. + for !is_blankz(parser.buffer, parser.buffer_pos) { + + // Check for 'x:x' in the flow context. TODO: Fix the test "spec-08-13". + if parser.flow_level > 0 && + parser.buffer[parser.buffer_pos] == ':' && + !is_blankz(parser.buffer, parser.buffer_pos+1) { + yaml_parser_set_scanner_error(parser, "while scanning a plain scalar", + start_mark, "found unexpected ':'") + return false + } + + // Check for indicators that may end a plain scalar. + if (parser.buffer[parser.buffer_pos] == ':' && is_blankz(parser.buffer, parser.buffer_pos+1)) || + (parser.flow_level > 0 && + (parser.buffer[parser.buffer_pos] == ',' || parser.buffer[parser.buffer_pos] == ':' || + parser.buffer[parser.buffer_pos] == '?' || parser.buffer[parser.buffer_pos] == '[' || + parser.buffer[parser.buffer_pos] == ']' || parser.buffer[parser.buffer_pos] == '{' || + parser.buffer[parser.buffer_pos] == '}')) { + break + } + + // Check if we need to join whitespaces and breaks. + if leading_blanks || len(whitespaces) > 0 { + if leading_blanks { + // Do we need to fold line breaks? + if leading_break[0] == '\n' { + if len(trailing_breaks) == 0 { + s = append(s, ' ') + } else { + s = append(s, trailing_breaks...) + } + } else { + s = append(s, leading_break...) + s = append(s, trailing_breaks...) + } + trailing_breaks = trailing_breaks[:0] + leading_break = leading_break[:0] + leading_blanks = false + } else { + s = append(s, whitespaces...) + whitespaces = whitespaces[:0] + } + } + + // Copy the character. + s = read(parser, s) + + end_mark = parser.mark + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + } + + // Is it the end? + if !(is_blank(parser.buffer, parser.buffer_pos) || is_break(parser.buffer, parser.buffer_pos)) { + break + } + + // Consume blank characters. + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + + for is_blank(parser.buffer, parser.buffer_pos) || is_break(parser.buffer, parser.buffer_pos) { + if is_blank(parser.buffer, parser.buffer_pos) { + + // Check for tab character that abuse indentation. + if leading_blanks && parser.mark.column < indent && is_tab(parser.buffer, parser.buffer_pos) { + yaml_parser_set_scanner_error(parser, "while scanning a plain scalar", + start_mark, "found a tab character that violate indentation") + return false + } + + // Consume a space or a tab character. + if !leading_blanks { + whitespaces = read(parser, whitespaces) + } else { + skip(parser) + } + } else { + if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) { + return false + } + + // Check if it is a first line break. + if !leading_blanks { + whitespaces = whitespaces[:0] + leading_break = read_line(parser, leading_break) + leading_blanks = true + } else { + trailing_breaks = read_line(parser, trailing_breaks) + } + } + if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) { + return false + } + } + + // Check indentation level. + if parser.flow_level == 0 && parser.mark.column < indent { + break + } + } + + // Create a token. + *token = yaml_token_t{ + typ: yaml_SCALAR_TOKEN, + start_mark: start_mark, + end_mark: end_mark, + value: s, + style: yaml_PLAIN_SCALAR_STYLE, + } + + // Note that we change the 'simple_key_allowed' flag. + if leading_blanks { + parser.simple_key_allowed = true + } + return true +} |