compiletest: Add AuxCrate struct with docs.

To make the code clearer.

src/tools/compiletest/src/directives.rs

@@ -8,8 +8,8 @@
 
 use crate::common::{CodegenBackend, Config, Debugger, FailMode, PassMode, RunFailMode, TestMode};
 use crate::debuggers::{extract_cdb_version, extract_gdb_version};
-pub(crate) use crate::directives::auxiliary::AuxProps;
 use crate::directives::auxiliary::parse_and_update_aux;
+pub(crate) use crate::directives::auxiliary::{AuxCrate, AuxProps};
 use crate::directives::directive_names::{
     KNOWN_DIRECTIVE_NAMES_SET, KNOWN_HTMLDOCCK_DIRECTIVE_NAMES, KNOWN_JSONDOCCK_DIRECTIVE_NAMES,
 };

src/tools/compiletest/src/directives/auxiliary.rs

@@ -7,6 +7,16 @@
 use crate::common::Config;
 use crate::directives::DirectiveLine;
 
+/// The value of an `aux-crate` directive.
+#[derive(Clone, Debug, Default)]
+pub struct AuxCrate {
+    /// With `aux-crate: foo=bar.rs` this will be `foo`.
+    /// With `aux-crate: noprelude:foo=bar.rs` this will be `noprelude:foo`.
+    pub name: String,
+    /// With `aux-crate: foo=bar.rs` this will be `bar.rs`.
+    pub path: String,
+}
+
 /// Properties parsed from `aux-*` test directives.
 #[derive(Clone, Debug, Default)]
 pub(crate) struct AuxProps {
@@ -17,7 +27,7 @@ pub(crate) struct AuxProps {
     pub(crate) bins: Vec<String>,
     /// Similar to `builds`, but a list of NAME=somelib.rs of dependencies
     /// to build and pass with the `--extern` flag.
-    pub(crate) crates: Vec<(String, String)>,
+    pub(crate) crates: Vec<AuxCrate>,
     /// Same as `builds`, but for proc-macros.
     pub(crate) proc_macros: Vec<String>,
     /// Similar to `builds`, but also uses the resulting dylib as a
@@ -34,7 +44,7 @@ pub(crate) fn all_aux_path_strings(&self) -> impl Iterator<Item = &str> {
         iter::empty()
             .chain(builds.iter().map(String::as_str))
             .chain(bins.iter().map(String::as_str))
-            .chain(crates.iter().map(|(_, path)| path.as_str()))
+            .chain(crates.iter().map(|c| c.path.as_str()))
             .chain(proc_macros.iter().map(String::as_str))
             .chain(codegen_backend.iter().map(String::as_str))
     }
@@ -63,10 +73,10 @@ pub(super) fn parse_and_update_aux(
     }
 }
 
-fn parse_aux_crate(r: String) -> (String, String) {
+fn parse_aux_crate(r: String) -> AuxCrate {
     let mut parts = r.trim().splitn(2, '=');
-    (
-        parts.next().expect("missing aux-crate name (e.g. log=log.rs)").to_string(),
-        parts.next().expect("missing aux-crate value (e.g. log=log.rs)").to_string(),
-    )
+    AuxCrate {
+        name: parts.next().expect("missing aux-crate name (e.g. log=log.rs)").to_string(),
+        path: parts.next().expect("missing aux-crate value (e.g. log=log.rs)").to_string(),
+    }
 }

src/tools/compiletest/src/runtest.rs

@@ -18,7 +18,7 @@
     TestSuite, UI_EXTENSIONS, UI_FIXED, UI_RUN_STDERR, UI_RUN_STDOUT, UI_STDERR, UI_STDOUT, UI_SVG,
     UI_WINDOWS_SVG, expected_output_path, incremental_dir, output_base_dir, output_base_name,
 };
-use crate::directives::TestProps;
+use crate::directives::{AuxCrate, TestProps};
 use crate::errors::{Error, ErrorKind, load_errors};
 use crate::output_capture::ConsoleOut;
 use crate::read2::{Truncated, read2_abbreviated};
@@ -1285,9 +1285,9 @@ fn build_all_auxiliary(&self, aux_dir: &Utf8Path, rustc: &mut Command) {
                 }
             };
 
-        for (aux_name, aux_path) in &self.props.aux.crates {
-            let aux_type = self.build_auxiliary(&aux_path, &aux_dir, None);
-            add_extern(rustc, aux_name, aux_path, aux_type);
+        for AuxCrate { name, path } in &self.props.aux.crates {
+            let aux_type = self.build_auxiliary(&path, &aux_dir, None);
+            add_extern(rustc, name, path, aux_type);
         }
 
         for proc_macro in &self.props.aux.proc_macros {