Merge pull request #13296 from xokdvium/empty-accessor-prefix

Clear `displayPrefix` in `makeEmptySourceAccessor`

Author: Mic92

src/libutil/memory-source-accessor.cc

@@ -187,6 +187,10 @@ void MemorySink::createSymlink(const CanonPath & path, const std::string & targe
 ref<SourceAccessor> makeEmptySourceAccessor()
 {
     static auto empty = make_ref<MemorySourceAccessor>().cast<SourceAccessor>();
+    /* Don't forget to clear the display prefix, as the default constructed
+       SourceAccessor has the «unknown» prefix. Since this accessor is supposed
+       to mimic an empty root directory the prefix needs to be empty. */
+    empty->setPathDisplay("");
     return empty;
 }
 

tests/functional/pure-eval.sh

@@ -34,3 +34,15 @@ rm -rf $TEST_ROOT/eval-out
 (! nix eval --store dummy:// --write-to $TEST_ROOT/eval-out --expr '{ "." = "bla"; }')
 
 (! nix eval --expr '~/foo')
+
+expectStderr 0 nix eval --expr "/some/absolute/path" \
+  | grepQuiet "/some/absolute/path"
+
+expectStderr 0 nix eval --expr "/some/absolute/path" --impure \
+  | grepQuiet "/some/absolute/path"
+
+expectStderr 0 nix eval --expr "some/relative/path" \
+  | grepQuiet "$PWD/some/relative/path"
+
+expectStderr 0 nix eval --expr "some/relative/path" --impure \
+  | grepQuiet "$PWD/some/relative/path"