Add a tidy rule to make sure that diagnostics don't end in periods

Author: compiler-errors

src/tools/tidy/Cargo.toml

@@ -13,6 +13,7 @@ ignore = "0.4.18"
 semver = "1.0"
 termcolor = "1.1.3"
 rustc-hash = "1.1.0"
+fluent-syntax = "0.11.1"
 
 [[bin]]
 name = "rust-tidy"

src/tools/tidy/src/fluent_period.rs

@@ -0,0 +1,84 @@
+//! Checks that no Fluent messages or attributes end in periods (except ellipses)
+
+use fluent_syntax::ast::{Entry,PatternElement};
+
+usecrate::walk::{filter_dirs, walk};
+use std::path::Path;
+
+fnfilter_fluent(path:&Path) -> bool{
+ifletSome(ext) = path.extension(){ ext.to_str() != Some("ftl")}else{true}
+}
+
+/// Messages allowed to have `.` at their end.
+///
+/// These should probably be reworked eventually.
+constALLOWLIST:&[&str] = &[
+"const_eval_long_running",
+"const_eval_validation_failure_note",
+"driver_impl_ice",
+"incremental_corrupt_file",
+"mir_build_pointer_pattern",
+];
+
+fncheck_period(filename:&str,contents:&str,bad:&mutbool){
+if filename.contains("codegen"){
+// FIXME: Too many codegen messages have periods right now...
+return;
+}
+
+let(Ok(parse) | Err((parse, _))) = fluent_syntax::parser::parse(contents);
+for entry in&parse.body{
+ifletEntry::Message(m) = entry {
+ifALLOWLIST.contains(&m.id.name){
+continue;
+}
+
+ifletSome(pat) = &m.value{
+ifletSome(PatternElement::TextElement{ value }) = pat.elements.last(){
+// We don't care about ellipses.
+if value.ends_with(".") && !value.ends_with("..."){
+let ll = find_line(contents,*value);
+let name = m.id.name;
+tidy_error!(bad,"{filename}:{ll}: message `{name}` ends in a period");
+}
+}
+}
+
+for attr in&m.attributes{
+// Teach notes usually have long messages.
+if attr.id.name == "teach_note"{
+continue;
+}
+
+ifletSome(PatternElement::TextElement{ value }) = attr.value.elements.last(){
+if value.ends_with(".") && !value.ends_with("..."){
+let ll = find_line(contents,*value);
+let name = attr.id.name;
+tidy_error!(bad,"{filename}:{ll}: attr `{name}` ends in a period");
+}
+}
+}
+}
+}
+}
+
+/// Evil cursed bad hack. Requires that `value` be a substr (in memory) of `contents`.
+fnfind_line(haystack:&str,needle:&str) -> usize{
+for(ll, line)in haystack.lines().enumerate(){
+if line.as_ptr() > needle.as_ptr(){
+return ll;
+}
+}
+
+1
+}
+
+pubfncheck(path:&Path,bad:&mutbool){
+walk(
+ path,
+ |path, is_dir| filter_dirs(path) || (!is_dir && filter_fluent(path)),
+&mut |ent, contents| {
+check_period(ent.path().to_str().unwrap(), contents, bad);
+},
+);
+}

src/tools/tidy/src/lib.rs

@@ -72,6 +72,7 @@ pub mod ext_tool_checks;
 pubmod extdeps;
 pubmod features;
 pubmod fluent_alphabetical;
+pubmod fluent_period;
 mod fluent_used;
 pub(crate)mod iter_header;
 pubmod known_bug;

src/tools/tidy/src/main.rs

@@ -115,6 +115,7 @@ fn main() {
 // Checks that only make sense for the compiler.
 check!(error_codes,&root_path,&[&compiler_path,&librustdoc_path], verbose);
 check!(fluent_alphabetical,&compiler_path, bless);
+check!(fluent_period,&compiler_path);
 check!(target_policy,&root_path);
 
 // Checks that only make sense for the std libs.