Merge pull request #34 from parcel-bundler/offset-utils

Offset utilities

.gitignore

@@ -12,3 +12,4 @@ prebuilds
 wasm-node
 wasm-browser
 yarn.lock
+.vscode/settings

src/MappingContainer.cpp

@@ -504,3 +504,45 @@ void MappingContainer::addIndexedMapping(int generatedLine, int generatedColumn,
 
     addMapping(generatedPosition, originalPosition, sourceIndex, nameIndex);
 }
+
+// TODO: This can be improved performance wise, by not having line stored in both MappingLine and Mapping
+void MappingContainer::offsetLines(int line, int lineOffset) {
+    int lineCount = this->_mapping_lines.size();
+
+    if (lineOffset > 0) {
+        this->createLinesIfUndefined(lineCount + lineOffset);
+
+        for (int lineIndex = lineCount - 1; lineIndex >= line; --lineIndex) {
+            std::vector<Mapping> mappings = this->_mapping_lines[lineIndex]._segments;
+            for (int mappingIndex = 0; mappingIndex < mappings.size(); ++mappingIndex) {
+                Mapping &mapping = mappings[mappingIndex];
+                Position generatedPosition = Position{mapping.generated.line + lineOffset, mapping.generated.column};
+                _mapping_lines[generatedPosition.line].addMapping(Mapping{generatedPosition, mapping.original, mapping.source, mapping.name});
+            }
+
+            this->_mapping_lines[lineIndex].clearMappings();
+        }
+    } else {
+        for (int lineIndex = line; lineIndex < lineCount; ++lineIndex) {
+            std::vector<Mapping> mappings = this->_mapping_lines[lineIndex]._segments;
+            for (int mappingIndex = 0; mappingIndex < mappings.size(); ++mappingIndex) {
+                Mapping &mapping = mappings[mappingIndex];
+                Position generatedPosition = Position{mapping.generated.line + lineOffset, mapping.generated.column};
+                _mapping_lines[generatedPosition.line].addMapping(Mapping{generatedPosition, mapping.original, mapping.source, mapping.name});
+            }
+
+            this->_mapping_lines[lineIndex].clearMappings();
+        }
+    }
+}
+
+void MappingContainer::offsetColumns(int line, int column, int columnOffset) {
+    auto mappingsCount = this->_mapping_lines[line]._segments.size();
+    for (int i = 0; i < mappingsCount; ++i) {
+        if (this->_mapping_lines[line]._segments[i].generated.column < column) {
+            continue;
+        }
+
+        this->_mapping_lines[line]._segments[i].generated.column += columnOffset;
+    }
+}

src/MappingContainer.h

@@ -52,14 +52,18 @@ class MappingContainer {
 
     Mapping findClosestMapping(int line, int column);
 
-    void addEmptyMap(std::string& sourceName, std::string &sourceContent, int lineOffset = 0);
+    void addEmptyMap(std::string &sourceName, std::string &sourceContent, int lineOffset = 0);
 
     flatbuffers::FlatBufferBuilder toBuffer();
 
     void extends(const void *buf);
 
     void addBufferMappings(const void *buf, int lineOffset = 0, int columnOffset = 0);
 
+    void offsetLines(int line, int lineOffset);
+
+    void offsetColumns(int line, int column, int columnOffset);
+
     void addIndexedMapping(int generatedLine, int generatedColumn, int originalLine, int originalColumn, std::string source, std::string name);
 
 private:

src/MappingLine.cpp

@@ -34,3 +34,7 @@ int MappingLine::lineNumber() {
     return _line_number;
 }
 
+void MappingLine::clearMappings() {
+    this->_segments.clear();
+    this->_last_column = 0;
+}

src/MappingLine.h

@@ -7,6 +7,8 @@ class MappingLine {
 
     void addMapping(Mapping m);
 
+    void clearMappings();
+
     void sort();
 
     bool isSorted();

src/SourceMap.js

@@ -277,6 +277,43 @@ export default class SourceMap {
     throw new Error('SourceMap.findClosestMapping() must be implemented when extending SourceMap');
   }
 
+  /**
+   * Offset mapping lines from a certain position
+   *
+   * @param line the line in the generated code (starts at 1)
+   * @param lineOffset the amount of lines to offset mappings by
+   */
+  offsetLines(line: number, lineOffset: number): ?IndexedMapping<string> {
+    if (line < 1 || line + lineOffset < 1) {
+      throw new Error('Line has to be positive');
+    }
+
+    if (lineOffset === 0) {
+      return;
+    }
+
+    this.sourceMapInstance.offsetLines(line - 1, lineOffset);
+  }
+
+  /**
+   * Offset mapping columns from a certain position
+   *
+   * @param line the line in the generated code (starts at 1)
+   * @param column the column in the generated code (starts at 0)
+   * @param columnOffset the amount of columns to offset mappings by
+   */
+  offsetColumns(line: number, column: number, columnOffset: number): ?IndexedMapping<string> {
+    if (line < 1 || column < 0 || column + columnOffset < 0) {
+      throw new Error('Line and Column has to be positive');
+    }
+
+    if (columnOffset === 0) {
+      return;
+    }
+
+    this.sourceMapInstance.offsetColumns(line - 1, column, columnOffset);
+  }
+
   /**
    * Returns a flatbuffer that represents this sourcemap, used for caching
    */

src/napi/SourceMap.cpp

@@ -413,7 +413,7 @@ Napi::Value SourceMapBinding::findClosestMapping(const Napi::CallbackInfo &info)
     Napi::HandleScope scope(env);
 
     if (info.Length() < 2 || !info[0].IsNumber() || !info[1].IsNumber()) {
-        Napi::TypeError::New(env, "Expected 1 parameter of type buffer").ThrowAsJavaScriptException();
+        Napi::TypeError::New(env, "Expected 2 parameters of type number").ThrowAsJavaScriptException();
         return env.Null();
     }
 
@@ -422,6 +422,30 @@ Napi::Value SourceMapBinding::findClosestMapping(const Napi::CallbackInfo &info)
     return _mappingToObject(env, m);
 }
 
+void SourceMapBinding::offsetLines(const Napi::CallbackInfo &info) {
+    Napi::Env env = info.Env();
+    Napi::HandleScope scope(env);
+
+    if (info.Length() < 2 || !info[0].IsNumber() || !info[1].IsNumber()) {
+        Napi::TypeError::New(env, "2 parameters of type number").ThrowAsJavaScriptException();
+        return;
+    }
+
+    _mapping_container.offsetLines(info[0].As<Napi::Number>().Int32Value(), info[1].As<Napi::Number>().Int32Value());
+}
+
+void SourceMapBinding::offsetColumns(const Napi::CallbackInfo &info) {
+    Napi::Env env = info.Env();
+    Napi::HandleScope scope(env);
+
+    if (info.Length() < 3 || !info[0].IsNumber() || !info[1].IsNumber() || !info[2].IsNumber()) {
+        Napi::TypeError::New(env, "3 parameters of type number").ThrowAsJavaScriptException();
+        return;
+    }
+
+    _mapping_container.offsetColumns(info[0].As<Napi::Number>().Int32Value(), info[1].As<Napi::Number>().Int32Value(), info[2].As<Napi::Number>().Int32Value());
+}
+
 Napi::Object SourceMapBinding::Init(Napi::Env env, Napi::Object exports) {
     Napi::HandleScope scope(env);
 
@@ -443,6 +467,8 @@ Napi::Object SourceMapBinding::Init(Napi::Env env, Napi::Object exports) {
             InstanceMethod("extends", &SourceMapBinding::extends),
             InstanceMethod("addEmptyMap", &SourceMapBinding::addEmptyMap),
             InstanceMethod("findClosestMapping", &SourceMapBinding::findClosestMapping),
+            InstanceMethod("offsetLines", &SourceMapBinding::offsetLines),
+            InstanceMethod("offsetColumns", &SourceMapBinding::offsetColumns),
     });
 
     exports.Set("SourceMap", func);

src/napi/SourceMap.h

@@ -25,6 +25,10 @@ class SourceMapBinding : public Napi::ObjectWrap<SourceMapBinding> {
 
     void setSourceContent(const Napi::CallbackInfo &info);
 
+    void offsetLines(const Napi::CallbackInfo &info);
+
+    void offsetColumns(const Napi::CallbackInfo &info);
+
     std::vector<int> _addSources(Napi::Array &sourcesArray, Napi::Array &sourcesContentArray);
 
     std::vector<int> _addNames(Napi::Array &namesArray);

src/wasm/SourceMap.cpp

@@ -129,6 +129,14 @@ Mapping SourceMap::findClosestMapping(int line, int column) {
     return _mapping_container.findClosestMapping(line - 1, column);
 }
 
+void SourceMap::offsetLines(int line, int lineOffset) {
+    _mapping_container.offsetLines(line, lineOffset);
+}
+
+void SourceMap::offsetColumns(int line, int column, int columnOffset) {
+    _mapping_container.offsetColumns(line, column, columnOffset);
+}
+
 EMSCRIPTEN_BINDINGS(my_class_example) {
     emscripten::register_vector<std::string>("VectorString");
     emscripten::register_vector<Mapping>("VectorMapping");
@@ -157,6 +165,8 @@ EMSCRIPTEN_BINDINGS(my_class_example) {
         .function("addEmptyMap", &SourceMap::addEmptyMap)
         .function("extends", &SourceMap::extends)
         .function("findClosestMapping", &SourceMap::findClosestMapping)
+        .function("offsetLines", &SourceMap::offsetLines)
+        .function("offsetColumns", &SourceMap::offsetColumns)
         ;
 
     emscripten::value_object<Mapping>("Mapping")

src/wasm/SourceMap.h

@@ -34,6 +34,9 @@ class SourceMap {
 
     Mapping findClosestMapping(int line, int column);
 
+    void offsetLines(int line, int lineOffset);
+    void offsetColumns(int line, int column, int columnOffset);
+
 private:
     MappingContainer _mapping_container;
 };