[PATCH] D137473: [vfs] Allow root paths relative to the directory of the vfsoverlay YAML file

[Ben Barham via Phabricator via cfe-commits]

bnbarham added a subscriber: dexonsmith.
bnbarham added a comment.

This seems reasonable to me in general. @dexonsmith in case you have any thoughts.



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Comment at: clang/test/VFS/Inputs/root-relative-overlay.yaml:4
+  'case-sensitive': false,
+  'overlay-relative': true,
+  'root-relative': 'yaml-dir',
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I'd prefer a test without `overlay-relative` set to make it clear they don't depend on each other.


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Comment at: llvm/include/llvm/Support/VirtualFileSystem.h:660
 ///   'use-external-names': <boolean, default=true>
+///   'root-relative': <string, one of 'cwd' or 'yaml-dir', default='cwd'>
 ///   'overlay-relative': <boolean, default=false>
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phosek wrote:
> Could we make this just a boolean akin to `overlay-relative` since there are only two options (default to `false`)?
I personally prefer being explicit here, `overlay-relative` is fairly confusing as it is.

`overlay-relative` isn't about allowing relative paths, but instead means that *all* external paths should be prefixed with the directory of the overlay. To put another way, external paths can be relative whether this is true/false, `overlay-relative` just *always* prepends the overlay path.

Could you add a comment to make it clear that this has no interaction with `overlay-relative`? If you want to add a comment to `overlay-relative` with something like the above that would also be appreciated :)


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Comment at: llvm/include/llvm/Support/VirtualFileSystem.h:752
+  enum class RootRelativeKind {
+    /// The roots are relative to the current working directory.
+    CWD,
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`to the current working directory when the overlay is created.` is maybe a little clearer to me


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Comment at: llvm/include/llvm/Support/VirtualFileSystem.h:755
+    /// The roots are relative to the directory where the YAML file locates.
+    YAMLDir
+  };
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Any thoughts on something like `OverlayDir` instead?


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Comment at: llvm/include/llvm/Support/VirtualFileSystem.h:926
+  /// is set. This will also be prefixed to each 'roots->name' if RootRelative
+  /// is set to RootRelativeKind::YAMLDir.
+  std::string YAMLFileDir;
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*and the path is relative*


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Comment at: llvm/lib/Support/VirtualFileSystem.cpp:1903
+        assert(!FullPath.empty() && "YAML file directory must exist");
+        sys::fs::make_absolute(FS->getYAMLFileDir(), Name);
+        Name = canonicalize(Name);
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IMO both this and CWD should be using the base FS instead. VFS didn't have a CWD previously, but now that it does it doesn't really make sense to use the process wide CWD. Especially since `-working-directory` doesn't change it.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D137473/new/

https://reviews.llvm.org/D137473