Overlapping selections are merged

spec/atom/editor-spec.coffee

@@ -757,7 +757,7 @@ describe "Editor", ->
         expect(range.end).toEqual({row: 5, column: 27})
         expect(editor.getCursorScreenPosition()).toEqual(row: 5, column: 27)
 
-  fdescribe "multiple cursor placement", ->
+  fdescribe "multiple cursors", ->
     it "places multiple cursor with meta-click", ->
       editor.attachToDom()
       editor.lines.trigger mousedownEvent(editor: editor, point: [3, 0])
@@ -919,6 +919,22 @@ describe "Editor", ->
         expect(selection1.getScreenRange()).toEqual [[4, 10], [5, 27]]
         expect(selection2.getScreenRange()).toEqual [[6, 10], [8, 27]]
 
+      describe "when multiple selctions intersect", ->
+        it "merges a selection that is completely contained within another", ->
+          editor.attachToDom()
+          editor.lines.trigger mousedownEvent(editor: editor, point: [4, 10])
+          editor.lines.trigger mousemoveEvent(editor: editor, point: [5, 27])
+          editor.lines.trigger 'mouseup'
+
+          editor.lines.trigger mousedownEvent(editor: editor, point: [3, 10], metaKey: true)
+          editor.lines.trigger mousemoveEvent(editor: editor, point: [6, 27], metaKey: true)
+          editor.lines.trigger 'mouseup'
+
+          selections = editor.compositeSelection.getSelections()
+          expect(selections.length).toBe 1
+          [selection1] = selections
+          expect(selection1.getScreenRange()).toEqual [[3, 10], [6, 27]]
+
     describe "cursor merging", ->
       it "merges cursors when they overlap due to a buffer change", ->
         editor.setCursorScreenPosition([0, 0])

spec/atom/range-spec.coffee

@@ -15,3 +15,18 @@ describe "Range", ->
       expect(new Range(new Point(1, 1), new Point(1, 1)).isEmpty()).toBeTruthy()
       expect(new Range(new Point(1, 1), new Point(1, 2)).isEmpty()).toBeFalsy()
 
+  describe ".intersectsWith(otherRange)", ->
+    it "returns true if the ranges intersect", ->
+      expect(new Range([1, 1], [2, 10]).intersectsWith(new Range([2, 1], [3, 10]))).toBeTruthy()
+      expect(new Range([2, 1], [3, 10]).intersectsWith(new Range([1, 1], [2, 10]))).toBeTruthy()
+      expect(new Range([2, 1], [3, 10]).intersectsWith(new Range([2, 5], [3, 1]))).toBeTruthy()
+      expect(new Range([2, 5], [3, 1]).intersectsWith(new Range([2, 1], [3, 10]))).toBeTruthy()
+      expect(new Range([2, 5], [3, 1]).intersectsWith(new Range([3, 2], [3, 10]))).toBeFalsy()
+      expect(new Range([3, 2], [3, 10]).intersectsWith(new Range([2, 5], [3, 1]))).toBeFalsy()
+
+  describe ".union(otherRange)", ->
+    it "returns the union of the two ranges", ->
+      expect(new Range([1, 1], [2, 10]).union(new Range([2, 1], [3, 10]))).toEqual [[1, 1], [3, 10]]
+      expect(new Range([2, 1], [3, 10]).union(new Range([1, 1], [2, 10]))).toEqual [[1, 1], [3, 10]]
+      expect(new Range([2, 1], [3, 10]).union(new Range([2, 5], [3, 1]))).toEqual [[2, 1], [3, 10]]
+      expect(new Range([2, 5], [3, 1]).union(new Range([2, 1], [3, 10]))).toEqual [[2, 1], [3, 10]]

spec/atom/range-spec.js

@@ -0,0 +1,42 @@
+(function() {
+  var Point, Range;
+
+  Range = require('range');
+
+  Point = require('point');
+
+  describe("Range", function() {
+    describe("constructor", function() {
+      return it("ensures that @start <= @end", function() {
+        var range1, range2;
+        range1 = new Range(new Point(0, 1), new Point(0, 4));
+        expect(range1.start).toEqual({
+          row: 0,
+          column: 1
+        });
+        range2 = new Range(new Point(1, 4), new Point(0, 1));
+        return expect(range2.start).toEqual({
+          row: 0,
+          column: 1
+        });
+      });
+    });
+    describe(".isEmpty()", function() {
+      return it("returns true if @start equals @end", function() {
+        expect(new Range(new Point(1, 1), new Point(1, 1)).isEmpty()).toBeTruthy();
+        return expect(new Range(new Point(1, 1), new Point(1, 2)).isEmpty()).toBeFalsy();
+      });
+    });
+    return describe(".intersectsWith(otherRange)", function() {
+      return fit("returns the intersection of the two ranges", function() {
+        var range1, range2;
+        range1 = new Range([1, 1], [2, 10]);
+        range2 = new Range([2, 1], [3, 10]);
+        expect(range1.intersectsWith(range2)).toBeTruth;
+        range2 = range1 = new Range([2, 1], [3, 10]);
+        return expect(range1.intersectsWith(range2)).toBeTruth;
+      });
+    });
+  });
+
+}).call(this);

src/atom/composite-selection.coffee

@@ -27,4 +27,14 @@ class CompositeSeleciton
       selection.backspace()
 
   selectToScreenPosition: (position) ->
-    _.last(@selections).selectToScreenPosition(position)
+    _.last(@selections).selectToScreenPosition(position)
+
+  mergeIntersectingSelections: ->
+    for selection in @getSelections()
+      otherSelections = @getSelections()
+      _.remove(otherSelections, selection)
+      for otherSelection in otherSelections
+        if selection.intersectsWith(otherSelection)
+          selection.merge(otherSelection)
+          @mergeIntersectingSelections()
+          return

src/atom/editor.coffee

@@ -166,7 +166,9 @@ class Editor extends View
   selectOnMousemoveUntilMouseup: ->
     moveHandler = (e) => @selectToScreenPosition(@screenPositionFromMouseEvent(e))
     @on 'mousemove', moveHandler
-    $(document).one 'mouseup', => @off 'mousemove', moveHandler
+    $(document).one 'mouseup', =>
+      @off 'mousemove', moveHandler
+      @compositeSelection.mergeIntersectingSelections()
 
   renderLines: ->
     @lineCache = []

src/atom/range.coffee

@@ -40,6 +40,17 @@ class Range
   inspect: ->
     "[#{@start.inspect()} - #{@end.inspect()}]"
 
+  intersectsWith: (otherRange) ->
+    if @start.isLessThanOrEqual(otherRange.start)
+      @end.isGreaterThan(otherRange.start)
+    else
+      otherRange.intersectsWith(this)
+
+  union: (otherRange) ->
+    start = if @start.isLessThan(otherRange.start) then @start else otherRange.start
+    end = if @end.isGreaterThan(otherRange.end) then @end else otherRange.end
+    new Range(start, end)
+
   isEmpty: ->
     @start.isEqual(@end)
 

src/atom/selection.coffee

@@ -92,6 +92,17 @@ class Selection extends View
   isEmpty: ->
     @getBufferRange().isEmpty()
 
+  intersectsWith: (otherSelection) ->
+    @getScreenRange().intersectsWith(otherSelection.getScreenRange())
+
+  merge: (otherSelection) ->
+    @setScreenRange(@getScreenRange().union(otherSelection.getScreenRange()))
+    otherSelection.remove()
+
+  remove: ->
+    @cursor?.remove()
+    super
+
   modifySelection: (fn) ->
     @placeAnchor()
     @modifyingSelection = true