Merge #8595

8595: Diagnostic paths support specifying `remapPrefix` r=rickvanprim a=rickvanprim

Currently VSCode Problem Matchers will resolve a path like `//foo_crate/src/main.rs` if `${workspaceFolder}/foo_crate/src/main.rs` exists.  Presumably their behavior is functionally a string concatenation that would produce `${workspaceFolder///foo_crate/src/main.rs` and repeated path separators get ignored.

This PR attempts to mimic this behavior by stripping any `Component::RootDir` from `file_name` before joining it to `workspace_root`, and then checking if the file exists.  If it does, this path is used, and if not, the behavior falls through to the existing Rust path join behavior.

Co-authored-by: James Leitch <[email protected]>

1 files changed, 6 insertions, 0 deletions

diff --git a/docs/user/generated_config.adoc b/docs/user/generated_config.adoc
index e0ee35b4e..e28423e99 100644
--- a/docs/user/generated_config.adoc
+++ b/docs/user/generated_config.adoc
@@ -147,6 +147,12 @@ have more false positives than usual.
 --
 List of rust-analyzer diagnostics to disable.
 --
+[[rust-analyzer.diagnostics.remapPrefix]]rust-analyzer.diagnostics.remapPrefix (default: `{}`)::
++
+--
+Map of prefixes to be substituted when parsing diagnostic file paths.
+This should be the reverse mapping of what is passed to `rustc` as `--remap-path-prefix`.
+--
 [[rust-analyzer.diagnostics.warningsAsHint]]rust-analyzer.diagnostics.warningsAsHint (default: `[]`)::
 +
 --