Allow customization of location dumping in ESTreeJSONDumper.

Summary: There are use cases for which we don't want to dump both "loc" and "range" in the AST. Allow this by making the API more flexible and introducing a LocationDumpMode. Reviewed By: tmikov Differential Revision: D23810725 fbshipit-source-id: 595920cd7113469e5b8111717a769df1ea1c09b5
Aliucord · Oct 6, 2020 · c3876bb · c3876bb
1 parent dd542ec
commit c3876bb
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Showing 2 changed files with 55 additions and 33 deletions.
diff --git a/include/hermes/AST/ESTreeJSONDumper.h b/include/hermes/AST/ESTreeJSONDumper.h
@@ -25,6 +25,16 @@ enum class ESTreeDumpMode {
   DumpAll,
 };
 
+/// Specifies which location information should be dumped by ESTreeJSONDumper.
+enum class LocationDumpMode {
+  /// Only output locations: line and column.
+  Loc,
+  /// Only output byte ranges.
+  Range,
+  /// Output both locations and byte ranges.
+  LocAndRange,
+};
+
 /// Print out the contents of the given tree to \p os.
 /// \p pretty for pretty print the JSON.
 /// When \p sm is not null, print the source locations for the AST nodes.
@@ -33,7 +43,8 @@ void dumpESTreeJSON(
     ESTree::NodePtr rootNode,
     bool pretty,
     ESTreeDumpMode mode,
-    SourceErrorManager *sm = nullptr);
+    SourceErrorManager *sm = nullptr,
+    LocationDumpMode locMode = LocationDumpMode::LocAndRange);
 
 /// Print out the contents of \p rootNode to \p json.
 /// Does not call json.endJSONL(), caller should do that if necessary.
@@ -42,7 +53,8 @@ void dumpESTreeJSON(
     JSONEmitter &json,
     ESTree::NodePtr rootNode,
     ESTreeDumpMode mode,
-    SourceErrorManager *sm = nullptr);
+    SourceErrorManager *sm = nullptr,
+    LocationDumpMode locMode = LocationDumpMode::LocAndRange);
 
 } // namespace hermes
 

diff --git a/lib/AST/ESTreeJSONDumper.cpp b/lib/AST/ESTreeJSONDumper.cpp
@@ -22,6 +22,7 @@ class ESTreeJSONDumper {
   JSONEmitter &json_;
   SourceErrorManager *sm_{nullptr};
   ESTreeDumpMode mode_;
+  LocationDumpMode locMode_;
 
   /// A collection of fields to ignore if they are empty (null or []).
   /// Mapping from node name to a set of ignored field names for that node.
@@ -31,8 +32,9 @@ class ESTreeJSONDumper {
   explicit ESTreeJSONDumper(
       JSONEmitter &json,
       SourceErrorManager *sm,
-      ESTreeDumpMode mode)
-      : json_(json), sm_(sm), mode_(mode) {
+      ESTreeDumpMode mode,
+      LocationDumpMode locMode)
+      : json_(json), sm_(sm), mode_(mode), locMode_(locMode) {
 #define ESTREE_NODE_0_ARGS(NAME, ...)
 #define ESTREE_NODE_1_ARGS(NAME, ...)
 #define ESTREE_NODE_2_ARGS(NAME, ...)
@@ -62,32 +64,38 @@ class ESTreeJSONDumper {
         !sm_->findBufferLineAndLoc(rng.End, end))
       return;
 
-    json_.emitKey("loc");
-    json_.openDict();
-    json_.emitKey("start");
-    json_.openDict();
-    json_.emitKeyValue("line", start.line);
-    json_.emitKeyValue("column", start.col);
-    json_.closeDict();
-    json_.emitKey("end");
-    json_.openDict();
-    json_.emitKeyValue("line", end.line);
-    json_.emitKeyValue("column", end.col);
-    json_.closeDict();
-    json_.closeDict();
+    if (locMode_ == LocationDumpMode::Loc ||
+        locMode_ == LocationDumpMode::LocAndRange) {
+      json_.emitKey("loc");
+      json_.openDict();
+      json_.emitKey("start");
+      json_.openDict();
+      json_.emitKeyValue("line", start.line);
+      json_.emitKeyValue("column", start.col);
+      json_.closeDict();
+      json_.emitKey("end");
+      json_.openDict();
+      json_.emitKeyValue("line", end.line);
+      json_.emitKeyValue("column", end.col);
+      json_.closeDict();
+      json_.closeDict();
+    }
 
-    const llvh::MemoryBuffer *buffer = sm_->findBufferForLoc(rng.Start);
-    assert(buffer && "The buffer must exist");
-    const char *bufStart = buffer->getBufferStart();
-    assert(
-        rng.Start.getPointer() >= bufStart &&
-        rng.End.getPointer() <= buffer->getBufferEnd() &&
-        "The range must be within the buffer");
-    json_.emitKey("range");
-    json_.openArray();
-    json_.emitValues(
-        {rng.Start.getPointer() - bufStart, rng.End.getPointer() - bufStart});
-    json_.closeArray();
+    if (locMode_ == LocationDumpMode::Range ||
+        locMode_ == LocationDumpMode::LocAndRange) {
+      const llvh::MemoryBuffer *buffer = sm_->findBufferForLoc(rng.Start);
+      assert(buffer && "The buffer must exist");
+      const char *bufStart = buffer->getBufferStart();
+      assert(
+          rng.Start.getPointer() >= bufStart &&
+          rng.End.getPointer() <= buffer->getBufferEnd() &&
+          "The range must be within the buffer");
+      json_.emitKey("range");
+      json_.openArray();
+      json_.emitValues(
+          {rng.Start.getPointer() - bufStart, rng.End.getPointer() - bufStart});
+      json_.closeArray();
+    }
   }
 
   void visit(Node *node, StringRef type) {
@@ -427,18 +435,20 @@ void dumpESTreeJSON(
     NodePtr rootNode,
     bool pretty,
     ESTreeDumpMode mode,
-    SourceErrorManager *sm) {
+    SourceErrorManager *sm,
+    LocationDumpMode locMode) {
   JSONEmitter json{os, pretty};
-  ESTreeJSONDumper(json, sm, mode).doIt(rootNode);
+  ESTreeJSONDumper(json, sm, mode, locMode).doIt(rootNode);
   json.endJSONL();
 }
 
 void dumpESTreeJSON(
     JSONEmitter &json,
     NodePtr rootNode,
     ESTreeDumpMode mode,
-    SourceErrorManager *sm) {
-  ESTreeJSONDumper(json, sm, mode).doIt(rootNode);
+    SourceErrorManager *sm,
+    LocationDumpMode locMode) {
+  ESTreeJSONDumper(json, sm, mode, locMode).doIt(rootNode);
 }
 
 } // namespace hermes