1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
//! The flow content type.
//!
//! **Flow** represents the sections, such as headings and code, which are
//! parsed per line.
//! An example is HTML, which has a certain starting condition (such as
//! `<script>` on its own line), then continues for a while, until an end
//! condition is found (such as `</style>`).
//! If that line with an end condition is never found, that flow goes until
//! the end.
//!
//! The constructs found in flow are:
//!
//! * [Blank line][crate::construct::blank_line]
//! * [Code (fenced)][crate::construct::code_fenced]
//! * [Code (indented)][crate::construct::code_indented]
//! * [Definition][crate::construct::definition]
//! * [Heading (atx)][crate::construct::heading_atx]
//! * [Heading (setext)][crate::construct::heading_setext]
//! * [HTML (flow)][crate::construct::html_flow]
//! * [Thematic break][crate::construct::thematic_break]
use crate::event::Name;
use crate::state::{Name as StateName, State};
use crate::tokenizer::Tokenizer;
/// Start of flow.
//
/// ```markdown
/// > | ## alpha
/// ^
/// > | bravo
/// ^
/// > | ***
/// ^
/// ```
pub fn start(tokenizer: &mut Tokenizer) -> State {
match tokenizer.current {
Some(b'`' | b'~') => {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeParagraph),
);
State::Retry(StateName::CodeFencedStart)
}
Some(b'<') => {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeParagraph),
);
State::Retry(StateName::HtmlFlowStart)
}
Some(b'#') => {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeParagraph),
);
State::Retry(StateName::HeadingAtxStart)
}
// Note: `-` is also used in thematic breaks, so it’s not included here.
Some(b'=') => {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeParagraph),
);
State::Retry(StateName::HeadingSetextStart)
}
Some(b'*' | b'_') => {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeParagraph),
);
State::Retry(StateName::ThematicBreakStart)
}
Some(b'[') => {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeParagraph),
);
State::Retry(StateName::DefinitionStart)
}
// Actual parsing: blank line? Indented code? Indented anything?
// Also includes `-` which can be a setext heading underline or a thematic break.
None | Some(b'\t' | b'\n' | b' ' | b'-') => State::Retry(StateName::FlowBlankLineBefore),
// Must be a paragraph.
Some(_) => {
tokenizer.attempt(State::Next(StateName::FlowAfter), State::Nok);
State::Retry(StateName::ParagraphStart)
}
}
}
/// At blank line.
///
/// ```markdown
/// > | ␠␠␊
/// ^
/// ```
pub fn blank_line_before(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowBlankLineAfter),
State::Next(StateName::FlowBeforeCodeIndented),
);
State::Retry(StateName::BlankLineStart)
}
/// At code (indented).
///
/// ```markdown
/// > | ␠␠␠␠a
/// ^
/// ```
pub fn before_code_indented(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeCodeFenced),
);
State::Retry(StateName::CodeIndentedStart)
}
/// At code (fenced).
///
/// ````markdown
/// > | ```
/// ^
/// ````
pub fn before_code_fenced(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeHtml),
);
State::Retry(StateName::CodeFencedStart)
}
/// At html (flow).
///
/// ```markdown
/// > | <a>
/// ^
/// ```
pub fn before_html(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeHeadingAtx),
);
State::Retry(StateName::HtmlFlowStart)
}
/// At heading (atx).
///
/// ```markdown
/// > | # a
/// ^
/// ```
pub fn before_heading_atx(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeHeadingSetext),
);
State::Retry(StateName::HeadingAtxStart)
}
/// At heading (setext).
///
/// ```markdown
/// | a
/// > | =
/// ^
/// ```
pub fn before_heading_setext(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeThematicBreak),
);
State::Retry(StateName::HeadingSetextStart)
}
/// At thematic break.
///
/// ```markdown
/// > | ***
/// ^
/// ```
pub fn before_thematic_break(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeDefinition),
);
State::Retry(StateName::ThematicBreakStart)
}
/// At definition.
///
/// ```markdown
/// > | [a]: b
/// ^
/// ```
pub fn before_definition(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(
State::Next(StateName::FlowAfter),
State::Next(StateName::FlowBeforeParagraph),
);
State::Retry(StateName::DefinitionStart)
}
/// At paragraph.
///
/// ```markdown
/// > | a
/// ^
/// ```
pub fn before_paragraph(tokenizer: &mut Tokenizer) -> State {
tokenizer.attempt(State::Next(StateName::FlowAfter), State::Nok);
State::Retry(StateName::ParagraphStart)
}
/// After blank line.
///
/// ```markdown
/// > | ␠␠␊
/// ^
/// ```
pub fn blank_line_after(tokenizer: &mut Tokenizer) -> State {
match tokenizer.current {
None => State::Ok,
Some(b'\n') => {
tokenizer.enter(Name::BlankLineEnding);
tokenizer.consume();
tokenizer.exit(Name::BlankLineEnding);
// Feel free to interrupt.
tokenizer.interrupt = false;
State::Next(StateName::FlowStart)
}
_ => unreachable!("expected eol/eof"),
}
}
/// After flow.
///
/// ```markdown
/// > | # a␊
/// ^
/// ```
pub fn after(tokenizer: &mut Tokenizer) -> State {
match tokenizer.current {
None => State::Ok,
Some(b'\n') => {
tokenizer.enter(Name::LineEnding);
tokenizer.consume();
tokenizer.exit(Name::LineEnding);
State::Next(StateName::FlowStart)
}
_ => unreachable!("expected eol/eof"),
}
}
|
