[GR-19220] Implement Module#const_source_location (#2212)

PullRequest: truffleruby/2365

Author: eregon

CHANGELOG.md

@@ -44,6 +44,7 @@ Compatibility:
 * Support the `inherit` parameter for `Module#{private, protected, public}_method_defined?`.
 * Implement `Thread.pending_interrupt?` and `Thread#pending_interrupt?` (#2219).
 * Implement `rb_lastline_set` (#2170).
+* Implemented `Module#const_source_location` (#2212, @tomstuart and @wildmaples).
 
 Performance:
 

spec/tags/core/module/const_source_location_tags.txt

@@ -1,32 +1,2 @@
-fails:Module#const_source_location return empty path if constant defined in C code
-fails:Module#const_source_location accepts a String or Symbol name
-fails:Module#const_source_location returns nil if no constant is defined in the search path
-fails:Module#const_source_location raises a NameError if the name contains non-alphabetic characters except '_'
 fails:Module#const_source_location calls #to_str to convert the given name to a String
-fails:Module#const_source_location raises a TypeError if conversion to a String by calling #to_str fails
-fails:Module#const_source_location does not search the singleton class of a Class or Module
-fails:Module#const_source_location does not search the containing scope
-fails:Module#const_source_location returns nil if the constant is defined in the receiver's superclass and the inherit flag is false
-fails:Module#const_source_location searches into the receiver superclasses if the inherit flag is true
-fails:Module#const_source_location returns nil when the receiver is a Module, the constant is defined at toplevel and the inherit flag is false
-fails:Module#const_source_location returns nil when the receiver is a Class, the constant is defined at toplevel and the inherit flag is false
-fails:Module#const_source_location accepts a toplevel scope qualifier
-fails:Module#const_source_location accepts a scoped constant name
-fails:Module#const_source_location does search private constants path
-fails:Module#const_source_location with dynamically assigned constants searches a path in the immediate class or module first
-fails:Module#const_source_location with dynamically assigned constants searches a path in a module included in the immediate class before the superclass
-fails:Module#const_source_location with dynamically assigned constants searches a path in the superclass before a module included in the superclass
-fails:Module#const_source_location with dynamically assigned constants searches a path in a module included in the superclass
-fails:Module#const_source_location with dynamically assigned constants searches a path in the superclass chain
-fails:Module#const_source_location with dynamically assigned constants returns path to a toplevel constant when the receiver is a Class
-fails:Module#const_source_location with dynamically assigned constants returns path to a toplevel constant when the receiver is a Module
-fails:Module#const_source_location with dynamically assigned constants returns path to the updated value of a constant
-fails:Module#const_source_location with statically assigned constants searches location path the immediate class or module first
-fails:Module#const_source_location with statically assigned constants searches location path a module included in the immediate class before the superclass
-fails:Module#const_source_location with statically assigned constants searches location path the superclass before a module included in the superclass
-fails:Module#const_source_location with statically assigned constants searches location path a module included in the superclass
-fails:Module#const_source_location with statically assigned constants searches location path the superclass chain
-fails:Module#const_source_location with statically assigned constants returns location path a toplevel constant when the receiver is a Class
-fails:Module#const_source_location with statically assigned constants returns location path a toplevel constant when the receiver is a Module
 fails:Module#const_source_location autoload returns the autoload location while not resolved
-fails:Module#const_source_location autoload returns where the constant was resolved when resolved

src/main/java/org/truffleruby/core/module/ModuleNodes.java

@@ -77,6 +77,7 @@
 import org.truffleruby.language.arguments.ReadPreArgumentNode;
 import org.truffleruby.language.arguments.ReadSelfNode;
 import org.truffleruby.language.arguments.RubyArguments;
+import org.truffleruby.language.backtrace.BacktraceFormatter;
 import org.truffleruby.language.constants.GetConstantNode;
 import org.truffleruby.language.constants.LookupConstantInterface;
 import org.truffleruby.language.constants.LookupConstantNode;
@@ -1072,6 +1073,62 @@ protected Object constMissing(RubyModule module, String name) {
 
     }
 
+    @CoreMethod(names = "const_source_location", required = 1, optional = 1)
+    @NodeChild(value = "module", type = RubyNode.class)
+    @NodeChild(value = "name", type = RubyNode.class)
+    @NodeChild(value = "inherit", type = RubyNode.class)
+    public abstract static class ConstSourceLocationNode extends CoreMethodNode {
+
+        @Child private MakeStringNode makeStringNode = MakeStringNode.create();
+
+        @CreateCast("name")
+        protected RubyNode coerceToStringOrSymbol(RubyNode name) {
+            return ToStringOrSymbolNodeGen.create(name);
+        }
+
+        @CreateCast("inherit")
+        protected RubyNode coerceToBoolean(RubyNode inherit) {
+            return BooleanCastWithDefaultNodeGen.create(true, inherit);
+        }
+
+        @Specialization(guards = { "strings.isRubyString(name)" })
+        @TruffleBoundary
+        protected Object constSourceLocation(RubyModule module, Object name, boolean inherit,
+                @CachedLibrary(limit = "2") RubyStringLibrary strings) {
+            final ConstantLookupResult lookupResult = ModuleOperations
+                    .lookupScopedConstant(getContext(), module, strings.getJavaString(name), inherit, this, true);
+
+            return getLocation(lookupResult);
+        }
+
+        @Specialization
+        @TruffleBoundary
+        protected Object constSourceLocation(RubyModule module, RubySymbol name, boolean inherit) {
+            final ConstantLookupResult lookupResult = ModuleOperations
+                    .lookupConstantWithInherit(getContext(), module, name.getString(), inherit, this, true);
+
+            return getLocation(lookupResult);
+        }
+
+        private Object getLocation(ConstantLookupResult lookupResult) {
+            if (!lookupResult.isFound()) {
+                return nil;
+            }
+
+            final SourceSection sourceSection = lookupResult.getConstant().getSourceSection();
+            if (!BacktraceFormatter.isAvailable(sourceSection)) {
+                return createEmptyArray();
+            } else {
+                final RubyString file = makeStringNode.executeMake(
+                        getContext().getSourcePath(sourceSection.getSource()),
+                        UTF8Encoding.INSTANCE,
+                        CodeRange.CR_UNKNOWN);
+                return createArray(new Object[]{ file, sourceSection.getStartLine() });
+            }
+        }
+
+    }
+
     @CoreMethod(names = "const_set", required = 2)
     @NodeChild(value = "module", type = RubyNode.class)
     @NodeChild(value = "name", type = RubyNode.class)