Read the whole test file before parsing directives

Few tests are larger than a handful of kilobytes, and nowadays we scan the
whole file for directives anyway, so there's little reason not to just read the
whole thing up-front.
This avoids having to deal with I/O within `iter_directives`, which should make
it easier to overhaul directive processing.

Author: Zalathar

src/tools/compiletest/src/directives.rs

@@ -1,9 +1,6 @@
 use std::collections::HashSet;
-use std::env;
-use std::fs::File;
-use std::io::BufReader;
-use std::io::prelude::*;
 use std::process::Command;
+use std::{env, fs};
 
 use camino::{Utf8Path,Utf8PathBuf};
 use semver::Version;
@@ -54,18 +51,19 @@ pub struct EarlyProps {
 
 implEarlyProps{
 pubfnfrom_file(config:&Config,testfile:&Utf8Path) -> Self{
-let file = File::open(testfile.as_std_path()).expect("open test file to parse earlyprops");
-Self::from_reader(config, testfile, file)
+let file_contents =
+ fs::read_to_string(testfile).expect("read test file to parse earlyprops");
+Self::from_file_contents(config, testfile,&file_contents)
 }
 
-pubfnfrom_reader<R:Read>(config:&Config,testfile:&Utf8Path,rdr:R) -> Self{
+pubfnfrom_file_contents(config:&Config,testfile:&Utf8Path,file_contents:&str) -> Self{
 letmut props = EarlyProps::default();
 letmut poisoned = false;
 iter_directives(
  config.mode,
 &mut poisoned,
  testfile,
-rdr,
+file_contents,
 // (dummy comment to force args into vertical layout)
 &mut |ref ln:DirectiveLine<'_>| {
 parse_and_update_aux(config, ln, testfile,&mut props.aux);
@@ -362,15 +360,15 @@ impl TestProps {
 fnload_from(&mutself,testfile:&Utf8Path,test_revision:Option<&str>,config:&Config){
 letmut has_edition = false;
 if !testfile.is_dir(){
-letfile = File::open(testfile.as_std_path()).unwrap();
+letfile_contents = fs::read_to_string(testfile).unwrap();
 
 letmut poisoned = false;
 
 iter_directives(
  config.mode,
 &mut poisoned,
  testfile,
-file,
+&file_contents,
 &mut |ref ln:DirectiveLine<'_>| {
 if !ln.applies_to_test_revision(test_revision){
 return;
@@ -859,7 +857,7 @@ fn iter_directives(
 mode:TestMode,
 poisoned:&mutbool,
 testfile:&Utf8Path,
-rdr:implRead,
+file_contents:&str,
 it:&mutdynFnMut(DirectiveLine<'_>),
 ){
 if testfile.is_dir(){
@@ -886,16 +884,7 @@ fn iter_directives(
 }
 }
 
-letmut rdr = BufReader::with_capacity(1024, rdr);
-letmut ln = String::new();
-letmut line_number = 0;
-
-loop{
- line_number += 1;
- ln.clear();
-if rdr.read_line(&mut ln).unwrap() == 0{
-break;
-}
+for(line_number, ln)in(1..).zip(file_contents.lines()){
 let ln = ln.trim();
 
 letSome(directive_line) = line_directive(line_number, ln)else{
@@ -1359,13 +1348,13 @@ where
 Some((min, max))
 }
 
-pub(crate)fnmake_test_description<R:Read>(
+pub(crate)fnmake_test_description(
 config:&Config,
 cache:&DirectivesCache,
 name:String,
 path:&Utf8Path,
 filterable_path:&Utf8Path,
-src:R,
+file_contents:&str,
 test_revision:Option<&str>,
 poisoned:&mutbool,
 ) -> CollectedTestDesc{
@@ -1380,7 +1369,7 @@ pub(crate) fn make_test_description<R: Read>(
  config.mode,
 &mut local_poisoned,
  path,
-src,
+file_contents,
 &mut |ref ln @ DirectiveLine{ line_number, .. }| {
 if !ln.applies_to_test_revision(test_revision){
 return;

src/tools/compiletest/src/directives/tests.rs

@@ -1,5 +1,3 @@
-use std::io::Read;
-
 use camino::Utf8Path;
 use semver::Version;
 
@@ -10,12 +8,12 @@ use crate::directives::{
 };
 usecrate::executor::{CollectedTestDesc,ShouldPanic};
 
-fnmake_test_description<R:Read>(
+fnmake_test_description(
 config:&Config,
 name:String,
 path:&Utf8Path,
 filterable_path:&Utf8Path,
-src:R,
+file_contents:&str,
 revision:Option<&str>,
 ) -> CollectedTestDesc{
 let cache = DirectivesCache::load(config);
@@ -26,7 +24,7 @@ fn make_test_description<R: Read>(
  name,
  path,
  filterable_path,
-src,
+file_contents,
  revision,
 &mut poisoned,
 );
@@ -226,14 +224,13 @@ fn cfg() -> ConfigBuilder {
 }
 
 fnparse_rs(config:&Config,contents:&str) -> EarlyProps{
-let bytes = contents.as_bytes();
-EarlyProps::from_reader(config,Utf8Path::new("a.rs"), bytes)
+EarlyProps::from_file_contents(config,Utf8Path::new("a.rs"), contents)
 }
 
 fncheck_ignore(config:&Config,contents:&str) -> bool{
 let tn = String::new();
 let p = Utf8Path::new("a.rs");
-let d = make_test_description(&config, tn, p, p,std::io::Cursor::new(contents),None);
+let d = make_test_description(&config, tn, p, p, contents,None);
  d.ignore
 }
 
@@ -243,9 +240,9 @@ fn should_fail() {
 let tn = String::new();
 let p = Utf8Path::new("a.rs");
 
-let d = make_test_description(&config, tn.clone(), p, p,std::io::Cursor::new(""),None);
+let d = make_test_description(&config, tn.clone(), p, p,"",None);
 assert_eq!(d.should_panic,ShouldPanic::No);
-let d = make_test_description(&config, tn, p, p,std::io::Cursor::new("//@ should-fail"),None);
+let d = make_test_description(&config, tn, p, p,"//@ should-fail",None);
 assert_eq!(d.should_panic,ShouldPanic::Yes);
 }
 
@@ -778,9 +775,8 @@ fn threads_support() {
 }
 }
 
-fnrun_path(poisoned:&mutbool,path:&Utf8Path,buf:&[u8]){
-let rdr = std::io::Cursor::new(&buf);
-iter_directives(TestMode::Ui, poisoned, path, rdr,&mut |_| {});
+fnrun_path(poisoned:&mutbool,path:&Utf8Path,file_contents:&str){
+iter_directives(TestMode::Ui, poisoned, path, file_contents,&mut |_| {});
 }
 
 #[test]
@@ -789,7 +785,7 @@ fn test_unknown_directive_check() {
 run_path(
 &mut poisoned,
 Utf8Path::new("a.rs"),
-include_bytes!("./test-auxillary/unknown_directive.rs"),
+include_str!("./test-auxillary/unknown_directive.rs"),
 );
 assert!(poisoned);
 }
@@ -800,7 +796,7 @@ fn test_known_directive_check_no_error() {
 run_path(
 &mut poisoned,
 Utf8Path::new("a.rs"),
-include_bytes!("./test-auxillary/known_directive.rs"),
+include_str!("./test-auxillary/known_directive.rs"),
 );
 assert!(!poisoned);
 }
@@ -811,7 +807,7 @@ fn test_error_annotation_no_error() {
 run_path(
 &mut poisoned,
 Utf8Path::new("a.rs"),
-include_bytes!("./test-auxillary/error_annotation.rs"),
+include_str!("./test-auxillary/error_annotation.rs"),
 );
 assert!(!poisoned);
 }
@@ -822,29 +818,29 @@ fn test_non_rs_unknown_directive_not_checked() {
 run_path(
 &mut poisoned,
 Utf8Path::new("a.Makefile"),
-include_bytes!("./test-auxillary/not_rs.Makefile"),
+include_str!("./test-auxillary/not_rs.Makefile"),
 );
 assert!(!poisoned);
 }
 
 #[test]
 fntest_trailing_directive(){
 letmut poisoned = false;
-run_path(&mut poisoned,Utf8Path::new("a.rs"),b"//@ only-x86 only-arm");
+run_path(&mut poisoned,Utf8Path::new("a.rs"),"//@ only-x86 only-arm");
 assert!(poisoned);
 }
 
 #[test]
 fntest_trailing_directive_with_comment(){
 letmut poisoned = false;
-run_path(&mut poisoned,Utf8Path::new("a.rs"),b"//@ only-x86 only-arm with comment");
+run_path(&mut poisoned,Utf8Path::new("a.rs"),"//@ only-x86 only-arm with comment");
 assert!(poisoned);
 }
 
 #[test]
 fntest_not_trailing_directive(){
 letmut poisoned = false;
-run_path(&mut poisoned,Utf8Path::new("a.rs"),b"//@ revisions: incremental");
+run_path(&mut poisoned,Utf8Path::new("a.rs"),"//@ revisions: incremental");
 assert!(!poisoned);
 }
 

src/tools/compiletest/src/lib.rs

@@ -892,7 +892,8 @@ fn make_test(cx: &TestCollectorCx, collector: &mut TestCollector, testpaths: &Te
 // `CollectedTest` that can be handed over to the test executor.
  collector.tests.extend(revisions.into_iter().map(|revision| {
 // Create a test name and description to hand over to the executor.
-let src_file = fs::File::open(&test_path).expect("open test file to parse ignores");
+let file_contents =
+ fs::read_to_string(&test_path).expect("read test file to parse ignores");
 let(test_name, filterable_path) =
 make_test_name_and_filterable_path(&cx.config, testpaths, revision);
 // Create a description struct for the test/revision.
@@ -904,7 +905,7 @@ fn make_test(cx: &TestCollectorCx, collector: &mut TestCollector, testpaths: &Te
  test_name,
 &test_path,
 &filterable_path,
-src_file,
+&file_contents,
  revision,
 &mut collector.poisoned,
 );