ironwork_syntax/
lib.rs

1//! ironwork for COBOL: from fixed-format source text to a syntax tree. Nothing here knows about
2//! storage or execution.
3
4pub mod ast;
5pub mod bms;
6pub mod copy;
7pub mod csd;
8mod debugging;
9pub mod dli;
10pub mod extended;
11pub mod feedback;
12pub mod jni;
13pub mod lexer;
14pub mod parser;
15pub mod report;
16pub mod source;
17pub mod sql;
18pub mod system;
19
20use std::fmt;
21
22pub use rt::vocab::Pos;
23
24/// The severity of a compiler message, IBM's five levels in order (Programming Guide SC27-8714-03,
25/// Table 38, p. 282).
26#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
27pub enum Severity {
28    /// I: the program runs correctly.
29    Informational,
30    /// W: a possible error; the program probably runs correctly.
31    Warning,
32    /// E: an error IBM's compiler corrects, though the program may not run as expected.
33    Error,
34    /// S: an error the compiler cannot correct; the program should not be run.
35    Severe,
36    /// U: the compilation ended.
37    Unrecoverable,
38}
39
40impl Severity {
41    /// The return code a compilation ends with when this is its most severe message.
42    pub const fn return_code(self) -> u8 {
43        match self {
44            Self::Informational => 0,
45            Self::Warning => 4,
46            Self::Error => 8,
47            Self::Severe => 12,
48            Self::Unrecoverable => 16,
49        }
50    }
51
52    /// The word a message's line carries after its position; an error's carries none.
53    pub const fn label(self) -> Option<&'static str> {
54        match self {
55            Self::Informational => Some("informational"),
56            Self::Warning => Some("warning"),
57            Self::Error | Self::Severe | Self::Unrecoverable => None,
58        }
59    }
60}
61
62/// A compiler message; [`Error::at`] makes a severe one.
63#[derive(Clone, Debug, PartialEq, Eq)]
64pub struct Error {
65    pub pos: Pos,
66    pub message: String,
67    /// The COPY member the position is in, when it is not the program itself.
68    pub file: Option<String>,
69    pub severity: Severity,
70}
71
72impl Error {
73    pub fn at(pos: Pos, message: impl Into<String>) -> Self {
74        Self { pos, message: message.into(), file: None, severity: Severity::Severe }
75    }
76
77    pub fn warning(pos: Pos, message: impl Into<String>) -> Self {
78        Self::at(pos, message).graded(Severity::Warning)
79    }
80
81    pub fn graded(mut self, severity: Severity) -> Self {
82        self.severity = severity;
83        self
84    }
85
86    /// Names the member a position in a COPY member came from.
87    pub fn in_files(mut self, files: &[String]) -> Self {
88        self.file = files.get(self.pos.file as usize).filter(|f| !f.is_empty()).cloned();
89        self
90    }
91
92    /// `file:line:col: message`, with `main` naming the program itself; a warning or informational
93    /// message puts its label before the message: `file:line:col: warning: message`.
94    pub fn place(&self, main: &str) -> String {
95        match (&self.file, self.pos.line) {
96            (Some(f), _) => format!("{f}:{self}"),
97            (None, 0) => format!("{main}: {}", self.labelled()),
98            (None, _) => format!("{main}:{self}"),
99        }
100    }
101
102    /// The message, after its severity's label when it has one.
103    pub fn labelled(&self) -> String {
104        match self.severity.label() {
105            Some(label) => format!("{label}: {}", self.message),
106            None => self.message.clone(),
107        }
108    }
109}
110
111impl fmt::Display for Error {
112    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
113        write!(f, "{}: {}", self.pos, self.labelled())
114    }
115}
116
117/// The return code of a compilation that gave these messages: the highest of theirs, 0 for none.
118pub fn return_code(messages: &[Error]) -> u8 {
119    messages.iter().map(|m| m.severity.return_code()).max().unwrap_or(0)
120}
121
122/// The message a refusal names: the first of the most severe.
123pub fn most_severe(messages: &[Error]) -> Option<&Error> {
124    messages.iter().rev().max_by_key(|m| m.severity)
125}
126
127impl std::error::Error for Error {}
128
129/// The first program in the source.
130pub fn parse(text: &str) -> Result<ast::Program, Error> {
131    parse_with(text, &copy::Libraries::default())
132}
133
134/// The first program in the source, with COPY members resolved from `libraries`.
135pub fn parse_with(text: &str, libraries: &copy::Libraries) -> Result<ast::Program, Error> {
136    Ok(parse_all_with(text, libraries)?.remove(0))
137}
138
139/// Every program in the source, in order, nested programs after the one that contains them. The
140/// libraries' compliance level says how the source and its members are read.
141pub fn parse_all_with(text: &str, libraries: &copy::Libraries) -> Result<Vec<ast::Program>, Error> {
142    let compliance = libraries.compliance();
143    let mut files = vec![String::new()];
144    let mut source = source::read_under(text, 0, false, compliance).and_then(|s| copy::expand(s, libraries, &mut files)).and_then(copy::replace).map_err(|e| e.in_files(&files))?;
145    let mut tokens = lexer::lex_under(&source, compliance).map_err(|e| e.in_files(&files))?;
146    if debugging::requested(&tokens) {
147        files.truncate(1);
148        source = source::read_under(text, 0, true, compliance).and_then(|s| copy::expand(s, libraries, &mut files)).and_then(copy::replace).map_err(|e| e.in_files(&files))?;
149        let lexed = lexer::lex_under(&source, compliance).map_err(|e| e.in_files(&files))?;
150        tokens = debugging::keep(lexed, source.debugging.as_deref().unwrap_or_default());
151    }
152    if compliance == numeric::Compliance::Extended {
153        tokens = extended::rewrite(tokens, &source.options).map_err(|e| e.in_files(&files))?;
154    }
155    let mut programs = parser::parse(&tokens, source.options).map_err(|e| e.in_files(&files))?;
156    for p in &mut programs {
157        p.sources = files.clone();
158    }
159    Ok(programs)
160}
161
162#[cfg(test)]
163mod tests {
164    use super::*;
165
166    const ALL: [Severity; 5] = [Severity::Informational, Severity::Warning, Severity::Error, Severity::Severe, Severity::Unrecoverable];
167
168    fn message(severity: Severity, line: u32) -> Error {
169        Error::at(Pos { file: 0, line, col: 8 }, format!("m{line}")).graded(severity)
170    }
171
172    #[test]
173    fn severities_rise_with_ibms_return_codes() {
174        assert_eq!(ALL.map(Severity::return_code), [0, 4, 8, 12, 16]);
175        assert!(ALL.windows(2).all(|w| w[0] < w[1]));
176        assert_eq!(Error::at(Pos::default(), "m").severity, Severity::Severe);
177        assert_eq!(Error::warning(Pos::default(), "m").severity, Severity::Warning);
178    }
179
180    #[test]
181    fn a_compilation_returns_the_highest_code_of_its_messages() {
182        let codes = |severities: &[Severity]| return_code(&severities.iter().enumerate().map(|(i, &s)| message(s, i as u32 + 1)).collect::<Vec<_>>());
183        use Severity::*;
184        assert_eq!(codes(&[]), 0);
185        assert_eq!(codes(&[Informational, Informational]), 0);
186        assert_eq!(codes(&[Informational, Warning]), 4);
187        assert_eq!(codes(&[Warning, Error, Informational]), 8);
188        assert_eq!(codes(&[Error, Severe, Warning]), 12);
189        assert_eq!(codes(&[Informational, Warning, Error, Severe]), 12);
190        assert_eq!(codes(&[Severe, Unrecoverable]), 16);
191    }
192
193    #[test]
194    fn the_message_a_refusal_names_is_the_first_of_the_most_severe() {
195        let messages = [message(Severity::Warning, 1), message(Severity::Severe, 2), message(Severity::Error, 3), message(Severity::Severe, 4)];
196        assert_eq!(most_severe(&messages).map(|m| m.pos.line), Some(2));
197        assert!(most_severe(&[]).is_none());
198    }
199
200    #[test]
201    fn an_error_line_carries_no_label_and_a_warning_or_informational_one_says_which_it_is() {
202        let lines: Vec<String> = ALL.map(|s| message(s, 7).place("p.cbl")).to_vec();
203        assert_eq!(lines, ["p.cbl:7:8: informational: m7", "p.cbl:7:8: warning: m7", "p.cbl:7:8: m7", "p.cbl:7:8: m7", "p.cbl:7:8: m7"]);
204        let unplaced = |s: Severity| Error::at(Pos::default(), "m").graded(s).place("p.cbl");
205        assert_eq!((unplaced(Severity::Severe), unplaced(Severity::Warning)), ("p.cbl: m".to_string(), "p.cbl: warning: m".to_string()));
206        let in_member = Error::warning(Pos { file: 1, line: 3, col: 8 }, "m3").in_files(&[String::new(), "COPYA".into()]);
207        assert_eq!(in_member.place("p.cbl"), "COPYA:3:8: warning: m3");
208        assert_eq!(message(Severity::Severe, 3).to_string(), "3:8: m3");
209    }
210}
ironwork_syntax/lib.rs

ironwork_syntax/
lib.rs
