compiletest/directives/
line.rs

1use std::fmt;
2
3use camino::Utf8Path;
4
5use crate::directives::LineNumber;
6
7const COMPILETEST_DIRECTIVE_PREFIX: &str = "//@";
8
9/// If the given line begins with the appropriate comment prefix for a directive,
10/// returns a struct containing various parts of the directive.
11pub(crate) fn line_directive<'a>(
12    file_path: &'a Utf8Path,
13    line_number: LineNumber,
14    original_line: &'a str,
15) -> Option<DirectiveLine<'a>> {
16    // Ignore lines that don't start with the comment prefix.
17    let after_comment =
18        original_line.trim_start().strip_prefix(COMPILETEST_DIRECTIVE_PREFIX)?.trim_start();
19
20    let revision;
21    let raw_directive;
22
23    if let Some(after_open_bracket) = after_comment.strip_prefix('[') {
24        // A comment like `//@[foo]` only applies to revision `foo`.
25        let Some((line_revision, after_close_bracket)) = after_open_bracket.split_once(']') else {
26            panic!(
27                "malformed condition directive: expected `{COMPILETEST_DIRECTIVE_PREFIX}[foo]`, found `{original_line}`"
28            )
29        };
30
31        revision = Some(line_revision);
32        raw_directive = after_close_bracket.trim_start();
33
34        if line_revision.contains(",") {
35            let suggestion: Vec<_> = line_revision
36                .split(",")
37                .map(|revision| {
38                    format!("{COMPILETEST_DIRECTIVE_PREFIX} [{revision}]: {raw_directive}")
39                })
40                .collect();
41            panic!(
42                "malformed condition directive: multiple revisions aren't supported yet in `{}`, split them like\n{}",
43                original_line,
44                suggestion.join("\n"),
45            );
46        }
47    } else {
48        revision = None;
49        raw_directive = after_comment;
50    };
51
52    // The directive name ends at the first occurrence of colon, space, or end-of-string.
53    let name = raw_directive.split([':', ' ']).next().expect("split is never empty");
54
55    Some(DirectiveLine { file_path, line_number, revision, raw_directive, name })
56}
57
58/// The (partly) broken-down contents of a line containing a test directive,
59/// which `iter_directives` passes to its callback function.
60///
61/// For example:
62///
63/// ```text
64/// //@ compile-flags: -O
65///     ^^^^^^^^^^^^^^^^^ raw_directive
66///     ^^^^^^^^^^^^^     name
67///
68/// //@ [foo] compile-flags: -O
69///      ^^^                    revision
70///           ^^^^^^^^^^^^^^^^^ raw_directive
71///           ^^^^^^^^^^^^^     name
72/// ```
73pub(crate) struct DirectiveLine<'a> {
74    /// Path of the file containing this line.
75    ///
76    /// Mostly used for diagnostics, but some directives (e.g. `//@ pp-exact`)
77    /// also use it to compute a value based on the filename.
78    pub(crate) file_path: &'a Utf8Path,
79    pub(crate) line_number: LineNumber,
80
81    /// Some test directives start with a revision name in square brackets
82    /// (e.g. `[foo]`), and only apply to that revision of the test.
83    /// If present, this field contains the revision name (e.g. `foo`).
84    pub(crate) revision: Option<&'a str>,
85
86    /// The main part of the directive, after removing the comment prefix
87    /// and the optional revision specifier.
88    ///
89    /// This is "raw" because the directive's name and colon-separated value
90    /// (if present) have not yet been extracted or checked.
91    raw_directive: &'a str,
92
93    /// Name of the directive.
94    ///
95    /// Invariant: `self.raw_directive.starts_with(self.name)`
96    pub(crate) name: &'a str,
97}
98
99impl<'ln> DirectiveLine<'ln> {
100    pub(crate) fn applies_to_test_revision(&self, test_revision: Option<&str>) -> bool {
101        self.revision.is_none() || self.revision == test_revision
102    }
103
104    /// Helper method used by `value_after_colon` and `remark_after_space`.
105    /// Don't call this directly.
106    fn rest_after_separator(&self, separator: u8) -> Option<&'ln str> {
107        let n = self.name.len();
108        if self.raw_directive.as_bytes().get(n) != Some(&separator) {
109            return None;
110        }
111
112        Some(&self.raw_directive[n + 1..])
113    }
114
115    /// If this directive uses `name: value` syntax, returns the part after
116    /// the colon character.
117    pub(crate) fn value_after_colon(&self) -> Option<&'ln str> {
118        self.rest_after_separator(b':')
119    }
120
121    /// If this directive uses `name remark` syntax, returns the part after
122    /// the separating space.
123    pub(crate) fn remark_after_space(&self) -> Option<&'ln str> {
124        self.rest_after_separator(b' ')
125    }
126
127    /// Allows callers to print `raw_directive` if necessary,
128    /// without accessing the field directly.
129    pub(crate) fn display(&self) -> impl fmt::Display {
130        self.raw_directive
131    }
132}
compiletest/directives/line.rs

compiletest/directives/
line.rs
