Add the remapping path documentation scope for rustdoc usage

compiler/rustc_session/src/config.rs

@@ -1322,6 +1322,7 @@ impl OutputFilenames {
 pub(crate) fn parse_remap_path_scope(
     early_dcx: &EarlyDiagCtxt,
     matches: &getopts::Matches,
+    unstable_opts: &UnstableOptions,
 ) -> RemapPathScopeComponents {
     if let Some(v) = matches.opt_str("remap-path-scope") {
         let mut slot = RemapPathScopeComponents::empty();
@@ -1329,11 +1330,18 @@ pub(crate) fn parse_remap_path_scope(
             slot |= match s {
                 "macro" => RemapPathScopeComponents::MACRO,
                 "diagnostics" => RemapPathScopeComponents::DIAGNOSTICS,
+                "documentation" => {
+                    if !unstable_opts.unstable_options {
+                        early_dcx.early_fatal("remapping `documentation` path scope requested but `-Zunstable-options` not specified");
+                    }
+
+                    RemapPathScopeComponents::DOCUMENTATION
+                },
                 "debuginfo" => RemapPathScopeComponents::DEBUGINFO,
                 "coverage" => RemapPathScopeComponents::COVERAGE,
                 "object" => RemapPathScopeComponents::OBJECT,
                 "all" => RemapPathScopeComponents::all(),
-                _ => early_dcx.early_fatal("argument for `--remap-path-scope` must be a comma separated list of scopes: `macro`, `diagnostics`, `debuginfo`, `coverage`, `object`, `all`"),
+                _ => early_dcx.early_fatal("argument for `--remap-path-scope` must be a comma separated list of scopes: `macro`, `diagnostics`, `documentation`, `debuginfo`, `coverage`, `object`, `all`"),
             }
         }
         slot
@@ -2677,7 +2685,7 @@ pub fn build_session_options(early_dcx: &mut EarlyDiagCtxt, matches: &getopts::M
     let externs = parse_externs(early_dcx, matches, &unstable_opts);
 
     let remap_path_prefix = parse_remap_path_prefix(early_dcx, matches, &unstable_opts);
-    let remap_path_scope = parse_remap_path_scope(early_dcx, matches);
+    let remap_path_scope = parse_remap_path_scope(early_dcx, matches, &unstable_opts);
 
     let pretty = parse_pretty(early_dcx, &unstable_opts);
 

compiler/rustc_span/src/lib.rs

@@ -233,6 +233,8 @@ bitflags::bitflags! {
         const DEBUGINFO = 1 << 3;
         /// Apply remappings to coverage information
         const COVERAGE = 1 << 4;
+        /// Apply remappings to documentation information
+        const DOCUMENTATION = 1 << 5;
 
         /// An alias for `macro`, `debuginfo` and `coverage`. This ensures all paths in compiled
         /// executables, libraries and objects are remapped but not elsewhere.

src/doc/rustc/src/remap-source-paths.md

@@ -52,7 +52,7 @@ The valid scopes are:
 - `debuginfo` - apply remappings to debug information
 - `coverage` - apply remappings to coverage information
 - `object` - apply remappings to all paths in compiled executables or libraries, but not elsewhere. Currently an alias for `macro,coverage,debuginfo`.
-- `all` (default) - an alias for all of the above, also equivalent to supplying only `--remap-path-prefix` without `--remap-path-scope`.
+- `all` (default) - an alias for all of the above (and unstable scopes), also equivalent to supplying only `--remap-path-prefix` without `--remap-path-scope`.
 
 The scopes accepted by `--remap-path-scope` are not exhaustive - new scopes may be added in future releases for eventual stabilisation.
 This implies that the `all` scope can correspond to different scopes between releases.

tests/run-make/remap-path-prefix/rmake.rs

@@ -12,7 +12,9 @@ fn main() {
     let mut out_simple = rustc();
     let mut out_object = rustc();
     let mut out_macro = rustc();
+    let mut out_doc = rustc();
     let mut out_diagobj = rustc();
+    let mut out_diagdocobj = rustc();
     out_simple
         .remap_path_prefix("auxiliary", "/the/aux")
         .crate_type("lib")
@@ -28,11 +30,21 @@ fn main() {
         .crate_type("lib")
         .emit("metadata")
         .input("auxiliary/lib.rs");
+    out_doc
+        .remap_path_prefix("auxiliary", "/the/aux")
+        .crate_type("lib")
+        .emit("metadata")
+        .input("auxiliary/lib.rs");
     out_diagobj
         .remap_path_prefix("auxiliary", "/the/aux")
         .crate_type("lib")
         .emit("metadata")
         .input("auxiliary/lib.rs");
+    out_diagdocobj
+        .remap_path_prefix("auxiliary", "/the/aux")
+        .crate_type("lib")
+        .emit("metadata")
+        .input("auxiliary/lib.rs");
 
     out_simple.run();
     rmeta_contains("/the/aux/lib.rs");
@@ -40,11 +52,17 @@ fn main() {
 
     out_object.arg("--remap-path-scope=object");
     out_macro.arg("--remap-path-scope=macro");
+    out_doc.arg("--remap-path-scope=documentation").arg("-Zunstable-options");
     out_diagobj.arg("--remap-path-scope=diagnostics,object");
+    out_diagdocobj
+        .arg("--remap-path-scope=diagnostics,documentation,object")
+        .arg("-Zunstable-options");
     if is_darwin() {
         out_object.arg("-Csplit-debuginfo=off");
         out_macro.arg("-Csplit-debuginfo=off");
+        out_doc.arg("-Csplit-debuginfo=off");
         out_diagobj.arg("-Csplit-debuginfo=off");
+        out_diagdocobj.arg("-Csplit-debuginfo=off");
     }
 
     out_object.run();
@@ -53,8 +71,14 @@ fn main() {
     out_macro.run();
     rmeta_contains("/the/aux/lib.rs");
     rmeta_contains("auxiliary");
+    out_doc.run();
+    rmeta_contains("/the/aux/lib.rs");
+    rmeta_contains("auxiliary");
     out_diagobj.run();
     rmeta_contains("/the/aux/lib.rs");
+    rmeta_contains("auxiliary");
+    out_diagdocobj.run();
+    rmeta_contains("/the/aux/lib.rs");
     rmeta_not_contains("auxiliary");
 }
 

tests/ui/feature-gates/remap-path-scope-documentation.rs

@@ -0,0 +1,7 @@
+// Test that documentation scope is unstable
+
+//@ compile-flags: --remap-path-scope=documentation
+
+//~? ERROR remapping `documentation` path scope requested but `-Zunstable-options` not specified
+
+fn main() {}

tests/ui/feature-gates/remap-path-scope-documentation.stderr

@@ -0,0 +1,2 @@
+error: remapping `documentation` path scope requested but `-Zunstable-options` not specified
+