[GR-18163] Fix the absolute path of the main script after chdir (#2709)

PullRequest: truffleruby/3468

Author: eregon

CHANGELOG.md

@@ -33,6 +33,7 @@ Compatibility:
 * Implement `rb_eval_cmd_kw` to support the `tk` gem (#2556, @aardvark179).
 * Fix `rb_class2name` to call `inspect` on anonymous classes like in CRuby (#2701, @aardvark179).
 * Implement `rb_ivar_foreach` to iterate over instance and class variables like in CRuby (#2701, @aardvark179).
+* Fix the absolute path of the main script after chdir (#2709, @eregon).
 
 Performance:
 

ci.jsonnet

@@ -543,8 +543,8 @@ local composition_environment = utils.add_inclusion_tracking(part_definitions, "
       "ruby-test-specs-darwin-aarch64-17": $.platform.darwin_aarch64 + $.jdk.v17 + $.env.jvm + gate_no_build + $.use.build + $.run.test_unit_tck + native_config + $.run.test_specs + { timelimit: "01:40:00" },
       "ruby-test-fast-linux-aarch64":   $.platform.linux_aarch64 + $.jdk.v11 + $.env.jvm + gate + $.run.test_fast + native_config + { timelimit: "45:00" },
       "ruby-test-fast-linux":           $.platform.linux  + $.jdk.v11 + $.env.jvm + gate + $.run.test_fast + { timelimit: "45:00" },  # To catch missing slow tags
-      "ruby-test-mri-linux":            $.platform.linux  + $.jdk.v11 + $.env.native + gate + $.run.test_mri + { timelimit: "01:10:00" },
-      "ruby-test-mri-linux-aarch64":    $.platform.linux_aarch64 + $.jdk.v11 + $.env.native + gate + $.run.test_mri + { timelimit: "01:10:00" },
+      "ruby-test-mri-linux":            $.platform.linux  + $.jdk.v11 + $.env.native + gate + $.run.test_mri + { timelimit: "01:20:00" },
+      "ruby-test-mri-linux-aarch64":    $.platform.linux_aarch64 + $.jdk.v11 + $.env.native + gate + $.run.test_mri + { timelimit: "01:20:00" },
       "ruby-test-mri-darwin-amd64":     $.platform.darwin_amd64 + $.jdk.v11 + $.env.native + gate + $.run.test_mri + { timelimit: "01:30:00" },
       "ruby-test-mri-darwin-aarch64":   $.platform.darwin_aarch64 + $.jdk.v11 + $.env.native + gate + $.run.test_mri + { timelimit: "01:30:00" },
       "ruby-test-integration-linux":    $.platform.linux  + $.jdk.v11 + $.env.jvm + gate + $.run.test_integration,

spec/ruby/core/thread/backtrace/location/absolute_path_spec.rb

@@ -17,6 +17,15 @@
     end
   end
 
+  it 'returns the correct absolute path when using a relative main script path and changing CWD' do
+    script = fixture(__FILE__, 'subdir/absolute_path_main_chdir.rb')
+    sibling = fixture(__FILE__, 'subdir/sibling.rb')
+    subdir = File.dirname script
+    Dir.chdir(fixture(__FILE__)) do
+      ruby_exe('subdir/absolute_path_main_chdir.rb').should == "subdir/absolute_path_main_chdir.rb\n#{subdir}\n#{subdir}\n#{script}\n#{sibling}\n"
+    end
+  end
+
   context "when used in eval with a given filename" do
     code = "caller_locations(0)[0].absolute_path"
 

spec/ruby/core/thread/backtrace/location/fixtures/subdir/absolute_path_main_chdir.rb

@@ -0,0 +1,11 @@
+puts __FILE__
+puts __dir__
+Dir.chdir __dir__
+
+# Check __dir__ is still correct after chdir
+puts __dir__
+
+puts caller_locations(0)[0].absolute_path
+
+# require_relative also needs to know the absolute path of the current file so we test it here too
+require_relative 'sibling'

spec/ruby/core/thread/backtrace/location/fixtures/subdir/sibling.rb

@@ -0,0 +1 @@
+puts __FILE__

spec/tags/core/thread/backtrace/location/absolute_path_tags.txt

@@ -1,2 +1,3 @@
 slow:Thread::Backtrace::Location#absolute_path returns an absolute path when using a relative main script path
 fails:Thread::Backtrace::Location#absolute_path canonicalization returns a canonical path without symlinks, even when __FILE__ is removed
+slow:Thread::Backtrace::Location#absolute_path returns the correct absolute path when using a relative main script path and changing CWD

src/main/java/org/truffleruby/core/kernel/KernelNodes.java

@@ -22,6 +22,7 @@
 import com.oracle.truffle.api.interop.InteropLibrary;
 import com.oracle.truffle.api.interop.UnsupportedMessageException;
 import com.oracle.truffle.api.object.PropertyGetter;
+import com.oracle.truffle.api.source.Source;
 import com.oracle.truffle.api.strings.AbstractTruffleString;
 import com.oracle.truffle.api.strings.TruffleString;
 import com.oracle.truffle.api.utilities.AssumedValue;
@@ -300,9 +301,9 @@ protected RubyString getCallerPath(Object feature,
                             coreExceptions().loadError("cannot infer basepath", featureString, this));
                 }
 
-                String sourcePath = getLanguage().getSourcePath(sourceSection.getSource());
-
-                sourcePath = getContext().getFeatureLoader().canonicalize(sourcePath);
+                Source source = sourceSection.getSource();
+                String sourcePath = getLanguage().getSourcePath(source);
+                sourcePath = getContext().getFeatureLoader().canonicalize(sourcePath, source);
 
                 featurePath = getContext().getFeatureLoader().dirname(sourcePath) + "/" + featureString;
             }
@@ -394,7 +395,7 @@ protected RubyString canonicalPath(Object string,
                 @Cached TruffleString.FromJavaStringNode fromJavaStringNode) {
             final String expandedPath = getContext()
                     .getFeatureLoader()
-                    .canonicalize(RubyGuards.getJavaString(string));
+                    .canonicalize(RubyGuards.getJavaString(string), null);
             return createString(fromJavaStringNode, expandedPath, Encodings.UTF_8);
         }
 

src/main/java/org/truffleruby/core/thread/ThreadBacktraceLocationNodes.java

@@ -66,7 +66,7 @@ public static Object getAbsolutePath(SourceSection sourceSection, RubyBaseNode n
                     return nil;
                 } else if (source.getPath() != null) { // A normal file
                     final String path = language.getSourcePath(source);
-                    final String canonicalPath = context.getFeatureLoader().canonicalize(path);
+                    final String canonicalPath = context.getFeatureLoader().canonicalize(path, source);
                     var cachedRope = language.tstringCache.getTString(TStringUtils.utf8TString(canonicalPath),
                             Encodings.UTF_8);
                     return node.createString(cachedRope, Encodings.UTF_8);

src/main/java/org/truffleruby/language/loader/FeatureLoader.java

@@ -64,6 +64,9 @@
 
 public class FeatureLoader {
 
+    private static final int PATH_MAX = 1024; // jnr-posix hard codes this value
+    private static final String[] EXTENSIONS = new String[]{ TruffleRuby.EXTENSION, RubyLanguage.CEXT_EXTENSION };
+
     private final RubyContext context;
     private final RubyLanguage language;
 
@@ -80,9 +83,9 @@ public class FeatureLoader {
 
     private String cwd = null;
     private Object getcwd;
-    private static final int PATH_MAX = 1024; // jnr-posix hard codes this value
 
-    private static final String[] EXTENSIONS = new String[]{ TruffleRuby.EXTENSION, RubyLanguage.CEXT_EXTENSION };
+    private Source mainScriptSource;
+    private String mainScriptAbsolutePath;
 
     public FeatureLoader(RubyContext context, RubyLanguage language) {
         this.context = context;
@@ -95,6 +98,13 @@ public void initialize(NativeConfiguration nativeConfiguration, TruffleNFIPlatfo
         }
     }
 
+    public void setMainScript(Source source, String absolutePath) {
+        assert mainScriptSource == null;
+        assert mainScriptAbsolutePath == null;
+        mainScriptSource = source;
+        mainScriptAbsolutePath = absolutePath;
+    }
+
     public void addAutoload(RubyConstant autoloadConstant) {
         final String autoloadPath = autoloadConstant.getAutoloadConstant().getAutoloadPath();
         final String basename = basenameWithoutExtension(autoloadPath);
@@ -229,7 +239,13 @@ private String makeAbsolute(String path) {
         }
     }
 
-    public String canonicalize(String path) {
+    public String canonicalize(String path, Source source) {
+        // Special case for the main script which has a relative Source#getPath():
+        // We need to resolve it correctly, even if the CWD changed since then.
+        if (source != null && source.equals(mainScriptSource)) {
+            return mainScriptAbsolutePath;
+        }
+
         // First, make the path absolute, by expanding relative to the context CWD
         // Otherwise, getCanonicalPath() uses user.dir as CWD which is incorrect.
         final String absolutePath = makeAbsolute(path);

src/main/java/org/truffleruby/language/loader/MainLoader.java

@@ -100,6 +100,8 @@ public RubySource loadFromFile(Env env, Node currentNode, String mainPath) throw
 
         final Source mainSource = fileLoader.buildSource(file, mainPath, sourceTString, false, true);
 
+        context.getFeatureLoader().setMainScript(mainSource, file.getCanonicalFile().getPath());
+
         return new RubySource(mainSource, mainPath, sourceTString);
     }