Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Detect invalid exprs in parser used by pretty-printer tests #134599

Merged
merged 4 commits into from
Dec 22, 2024
Merged

Detect invalid exprs in parser used by pretty-printer tests #134599

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
3f98f76
Check that pretty-printer parenthesis test operates on the whole test…
dtolnay Dec 21, 2024
65ba6ac
Extract ui-fulldeps expression parser into module
dtolnay Dec 21, 2024
822e806
Switch pretty-printer roundtrip test to better parser
dtolnay Dec 21, 2024
1f2028f
Show which test case was found to be meaningless
dtolnay Dec 21, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
51 changes: 51 additions & 0 deletions tests/ui-fulldeps/auxiliary/parser.rs
View file
Open in desktop
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

In both pprust-*.rs tests, I think I would rather use //@ aux-crate: parser=parser.rs //@ edition: 2021 (aux-crate puts the crate into the extern prelude contrary to aux-build) instead of fighting against compiletest (#[path = "auxiliary/parser.rs"] mod parser;). The extra overhead is not really relevant.

Original file line number Diff line number Diff line change
@@ -0,0 +1,51 @@
#![feature(rustc_private)]

extern crate rustc_ast;
extern crate rustc_driver;
extern crate rustc_errors;
extern crate rustc_parse;
extern crate rustc_session;
extern crate rustc_span;

use rustc_ast::ast::{DUMMY_NODE_ID, Expr};
use rustc_ast::mut_visit::MutVisitor;
use rustc_ast::node_id::NodeId;
use rustc_ast::ptr::P;
use rustc_ast::token;
use rustc_errors::Diag;
use rustc_parse::parser::Recovery;
use rustc_session::parse::ParseSess;
use rustc_span::{DUMMY_SP, FileName, Span};

pub fn parse_expr(psess: &ParseSess, source_code: &str) -> Option<P<Expr>> {
let parser = rustc_parse::unwrap_or_emit_fatal(rustc_parse::new_parser_from_source_str(
psess,
FileName::anon_source_code(source_code),
source_code.to_owned(),
));

let mut parser = parser.recovery(Recovery::Forbidden);
let mut expr = parser.parse_expr().map_err(Diag::cancel).ok()?;
if parser.token != token::Eof {
return None;
}

Normalize.visit_expr(&mut expr);
Some(expr)
}

// Erase Span information that could distinguish between identical expressions
// parsed from different source strings.
struct Normalize;

impl MutVisitor for Normalize {
const VISIT_TOKENS: bool = true;

fn visit_id(&mut self, id: &mut NodeId) {
*id = DUMMY_NODE_ID;
}

fn visit_span(&mut self, span: &mut Span) {
*span = DUMMY_SP;
}
}
18 changes: 4 additions & 14 deletions tests/ui-fulldeps/pprust-expr-roundtrip.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,5 +1,7 @@
//@ run-pass
//@ ignore-cross-compile
//@ aux-crate: parser=parser.rs
//@ edition: 2021

// The general idea of this test is to enumerate all "interesting" expressions and check that
// `parse(print(e)) == e` for all `e`. Here's what's interesting, for the purposes of this test:
Expand All @@ -21,7 +23,6 @@

extern crate rustc_ast;
extern crate rustc_ast_pretty;
extern crate rustc_data_structures;
extern crate rustc_parse;
extern crate rustc_session;
extern crate rustc_span;
Expand All @@ -32,28 +33,17 @@ extern crate thin_vec;
#[allow(unused_extern_crates)]
extern crate rustc_driver;

use parser::parse_expr;
use rustc_ast::mut_visit::{visit_clobber, MutVisitor};
use rustc_ast::ptr::P;
use rustc_ast::*;
use rustc_ast_pretty::pprust;
use rustc_parse::{new_parser_from_source_str, unwrap_or_emit_fatal};
use rustc_session::parse::ParseSess;
use rustc_span::source_map::Spanned;
use rustc_span::symbol::Ident;
use rustc_span::{FileName, DUMMY_SP};
use rustc_span::DUMMY_SP;
use thin_vec::{thin_vec, ThinVec};

fn parse_expr(psess: &ParseSess, src: &str) -> Option<P<Expr>> {
let src_as_string = src.to_string();

let mut p = unwrap_or_emit_fatal(new_parser_from_source_str(
psess,
FileName::Custom(src_as_string.clone()),
src_as_string,
));
p.parse_expr().map_err(|e| e.cancel()).ok()
}

// Helper functions for building exprs
fn expr(kind: ExprKind) -> P<Expr> {
P(Expr { id: DUMMY_NODE_ID, kind, span: DUMMY_SP, attrs: AttrVec::new(), tokens: None })
Expand Down
43 changes: 7 additions & 36 deletions tests/ui-fulldeps/pprust-parenthesis-insertion.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,5 +1,7 @@
//@ run-pass
//@ ignore-cross-compile
//@ aux-crate: parser=parser.rs
//@ edition: 2021

// This test covers the AST pretty-printer's automatic insertion of parentheses
// into unparenthesized syntax trees according to precedence and various grammar
Expand Down Expand Up @@ -31,24 +33,19 @@

extern crate rustc_ast;
extern crate rustc_ast_pretty;
extern crate rustc_driver;
extern crate rustc_errors;
extern crate rustc_parse;
extern crate rustc_session;
extern crate rustc_span;

use std::mem;
use std::process::ExitCode;

use rustc_ast::ast::{DUMMY_NODE_ID, Expr, ExprKind};
use parser::parse_expr;
use rustc_ast::ast::{Expr, ExprKind};
use rustc_ast::mut_visit::{self, DummyAstNode as _, MutVisitor};
use rustc_ast::node_id::NodeId;
use rustc_ast::ptr::P;
use rustc_ast_pretty::pprust;
use rustc_errors::Diag;
use rustc_parse::parser::Recovery;
use rustc_session::parse::ParseSess;
use rustc_span::{DUMMY_SP, FileName, Span};

// Every parenthesis in the following expressions is re-inserted by the
// pretty-printer.
Expand Down Expand Up @@ -154,34 +151,6 @@ impl MutVisitor for Unparenthesize {
}
}

// Erase Span information that could distinguish between identical expressions
// parsed from different source strings.
struct Normalize;

impl MutVisitor for Normalize {
const VISIT_TOKENS: bool = true;

fn visit_id(&mut self, id: &mut NodeId) {
*id = DUMMY_NODE_ID;
}

fn visit_span(&mut self, span: &mut Span) {
*span = DUMMY_SP;
}
}

fn parse_expr(psess: &ParseSess, source_code: &str) -> Option<P<Expr>> {
let parser = rustc_parse::unwrap_or_emit_fatal(rustc_parse::new_parser_from_source_str(
psess,
FileName::anon_source_code(source_code),
source_code.to_owned(),
));

let mut expr = parser.recovery(Recovery::Forbidden).parse_expr().map_err(Diag::cancel).ok()?;
Normalize.visit_expr(&mut expr);
Some(expr)
}

fn main() -> ExitCode {
let mut status = ExitCode::SUCCESS;
let mut fail = |description: &str, before: &str, after: &str| {
Expand All @@ -197,7 +166,9 @@ fn main() -> ExitCode {
let psess = &ParseSess::new(vec![rustc_parse::DEFAULT_LOCALE_RESOURCE]);

for &source_code in EXPRS {
let expr = parse_expr(psess, source_code).unwrap();
let Some(expr) = parse_expr(psess, source_code) else {
panic!("Failed to parse original test case: {source_code}");
};

// Check for FALSE POSITIVE: pretty-printer inserting parentheses where not needed.
// Pseudocode:
Expand Down
Loading