Rollup merge of #133470 - jieyouxu:ugly, r=compiler-errors

Cleanup: delete `//@ pretty-expanded` directive

This PR removes the `//@ pretty-expanded` directive support in compiletest and removes its usage inside ui tests because it does not actually do anything, and its existence is itself misleading. This PR is split into two commits:

1. The first commit just drops `pretty-expanded` directive support in compiletest.
2. The second commit is created by `sd '//@ pretty-expanded.*\n' '' tests/ui/**/*.rs`[^1], reblessing, and slightly adjusting some leading whitespace in a few tests.

We can tell this is fully removed because compiletest doesn't complain about unknown directive when running the `ui` test suite.

cc #23616

### History

Originally, there was some effort to introduce more test coverage for `-Z unpretty=expanded` (in 2015 this was called `--pretty=expanded`). In [Make it an error to not declare used features #23598][pr-23598], there was a flip from `//@ no-pretty-expanded` (opt-out of `-Z
unpretty=expanded` test) to `//@ pretty-expanded` (opt-in to `-Z unpretty=expanded` test). This was needed because back then the dedicated `tests/pretty` ("pretty") test suite did not existed, and the pretty tests were grouped together under `run-pass` tests (I believe the `ui` test suite didn't exist back then either). Unfortunately, in this process the replacement `//@ pretty-expanded` directives contained a `FIXME #23616` linking to [There are very few tests for `-Z unpretty` expansion #23616][issue-23616]. But this was arguably backwards and somewhat misleading, as noted in [#23616](#23616 (comment)):

    The attribute is off by default and things just work if you don't
    test it, people have not been adding the `pretty-expanded`
    annotation to new tests even if it would work.

Which basically renders this useless.

### Current status

As of Nov 2024, we have a dedicated `pretty` test suite, and some time over the years the split between `run-pass` into `ui` and `pretty` test suites caused all the `//@ pretty-expanded` in `ui` tests to do absolutely nothing: the compiletest logic for `pretty-expanded` only triggers in the *pretty* test suite, but none of the pretty tests use it. Oops.

Nobody remembers this, nobody uses this, it's misleading in ui tests. Let's get rid of this directive altogether.

[pr-23598]: #23598
[issue-23616]: #23616

### Follow-ups

- [x] Yeet this directive from rustc-dev-guide docs. rust-lang/rustc-dev-guide#2147

[^1]: https://github.com/chmln/sd

r? compiler

Author: GuillaumeGomez

src/tools/compiletest/src/directive-list.rs

@@ -214,7 +214,6 @@ const KNOWN_DIRECTIVE_NAMES: &[&str] = &[
     "only-x86_64-unknown-linux-gnu",
     "pp-exact",
     "pretty-compare-only",
-    "pretty-expanded",
     "pretty-mode",
     "reference",
     "regex-error-pattern",

src/tools/compiletest/src/header.rs

@@ -124,8 +124,6 @@ pub struct TestProps {
     // a proc-macro and needs `#![crate_type = "proc-macro"]`. This ensures
     // that the aux file is compiled as a `proc-macro` and not as a `dylib`.
     pub no_prefer_dynamic: bool,
-    // Run -Zunpretty expanded when running pretty printing tests
-    pub pretty_expanded: bool,
     // Which pretty mode are we testing with, default to 'normal'
     pub pretty_mode: String,
     // Only compare pretty output and don't try compiling
@@ -218,7 +216,6 @@ mod directives {
     pub const DONT_CHECK_COMPILER_STDOUT: &'static str = "dont-check-compiler-stdout";
     pub const DONT_CHECK_COMPILER_STDERR: &'static str = "dont-check-compiler-stderr";
     pub const NO_PREFER_DYNAMIC: &'static str = "no-prefer-dynamic";
-    pub const PRETTY_EXPANDED: &'static str = "pretty-expanded";
     pub const PRETTY_MODE: &'static str = "pretty-mode";
     pub const PRETTY_COMPARE_ONLY: &'static str = "pretty-compare-only";
     pub const AUX_BIN: &'static str = "aux-bin";
@@ -278,7 +275,6 @@ impl TestProps {
             dont_check_compiler_stderr: false,
             compare_output_lines_by_subset: false,
             no_prefer_dynamic: false,
-            pretty_expanded: false,
             pretty_mode: "normal".to_string(),
             pretty_compare_only: false,
             forbid_output: vec![],
@@ -425,7 +421,6 @@ impl TestProps {
                         &mut self.dont_check_compiler_stderr,
                     );
                     config.set_name_directive(ln, NO_PREFER_DYNAMIC, &mut self.no_prefer_dynamic);
-                    config.set_name_directive(ln, PRETTY_EXPANDED, &mut self.pretty_expanded);
 
                     if let Some(m) = config.parse_name_value_directive(ln, PRETTY_MODE) {
                         self.pretty_mode = m;

src/tools/compiletest/src/runtest/pretty.rs

@@ -84,21 +84,5 @@ impl TestCx<'_> {
         if !proc_res.status.success() {
             self.fatal_proc_rec("pretty-printed source does not typecheck", &proc_res);
         }
-
-        if !self.props.pretty_expanded {
-            return;
-        }
-
-        // additionally, run `-Zunpretty=expanded` and try to build it.
-        let proc_res = self.print_source(ReadFrom::Path, "expanded");
-        if !proc_res.status.success() {
-            self.fatal_proc_rec("pretty-printing (expanded) failed", &proc_res);
-        }
-
-        let ProcRes { stdout: expanded_src, .. } = proc_res;
-        let proc_res = self.typecheck_source(expanded_src);
-        if !proc_res.status.success() {
-            self.fatal_proc_rec("pretty-printed source (expanded) does not typecheck", &proc_res);
-        }
     }
 }

tests/ui/abi/anon-extern-mod.rs

@@ -1,5 +1,4 @@
 //@ run-pass
-//@ pretty-expanded FIXME #23616
 
 #[link(name = "rust_test_helpers", kind = "static")]
 extern "C" {

tests/ui/abi/c-stack-as-value.rs

@@ -1,5 +1,4 @@
 //@ run-pass
-//@ pretty-expanded FIXME #23616
 
 mod rustrt {
     #[link(name = "rust_test_helpers", kind = "static")]

tests/ui/abi/cross-crate/anon-extern-mod-cross-crate-2.rs

@@ -1,6 +1,5 @@
 //@ run-pass
 //@ aux-build:anon-extern-mod-cross-crate-1.rs
-//@ pretty-expanded FIXME #23616
 
 extern crate anonexternmod;
 

tests/ui/abi/cross-crate/duplicated-external-mods.rs

@@ -1,7 +1,6 @@
 //@ run-pass
 //@ aux-build:anon-extern-mod-cross-crate-1.rs
 //@ aux-build:anon-extern-mod-cross-crate-1.rs
-//@ pretty-expanded FIXME #23616
 
 extern crate anonexternmod;
 

tests/ui/abi/extern/extern-pass-empty.rs

@@ -3,7 +3,6 @@
 
 // Test a foreign function that accepts empty struct.
 
-//@ pretty-expanded FIXME #23616
 //@ ignore-msvc
 //@ ignore-emscripten emcc asserts on an empty struct as an argument
 

tests/ui/abi/foreign/invoke-external-foreign.rs

@@ -5,7 +5,6 @@
 // successfully (and safely) invoke external, cdecl
 // functions from outside the crate.
 
-//@ pretty-expanded FIXME #23616
 
 extern crate foreign_lib;
 

tests/ui/alias-uninit-value.rs

@@ -7,7 +7,6 @@
 
 // Regression test for issue #374
 
-//@ pretty-expanded FIXME #23616
 
 enum sty { ty_nil, }