From 450d6b12fa03fe99805848b57e64b7113a7a9396 Mon Sep 17 00:00:00 2001
From: Antonio Scandurra <as-cii@github.com>
Date: Tue, 9 Jan 2018 16:47:26 +0100
Subject: [PATCH] Don't add fully-contained selections above/below

This is slower than it needs to be and creates behavioral problems when
selections get merged in some cases.

Signed-off-by: Nathan Sobo <nathan@github.com>
---
 spec/text-editor-spec.js | 26 ++++++++++++++++++++++++++
 src/selection.js         | 16 ++++++++++++----
 2 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/spec/text-editor-spec.js b/spec/text-editor-spec.js
index 328b7e8c4..a9aa80cd1 100644
--- a/spec/text-editor-spec.js
+++ b/spec/text-editor-spec.js
@@ -2376,6 +2376,19 @@ describe('TextEditor', () => {
           ])
         })
       })
+
+      it('does not create a new selection if it would be fully contained within another selection', () => {
+        editor.setText('abc\ndef\nghi\njkl\nmno')
+        editor.setCursorBufferPosition([0, 1])
+
+        let addedSelectionCount = 0
+        editor.onDidAddSelection(() => { addedSelectionCount++ })
+
+        editor.addSelectionBelow()
+        editor.addSelectionBelow()
+        editor.addSelectionBelow()
+        expect(addedSelectionCount).toBe(3)
+      })
     })
 
     describe('.addSelectionAbove()', () => {
@@ -2498,6 +2511,19 @@ describe('TextEditor', () => {
           ])
         })
       })
+
+      it('does not create a new selection if it would be fully contained within another selection', () => {
+        editor.setText('abc\ndef\nghi\njkl\nmno')
+        editor.setCursorBufferPosition([4, 1])
+
+        let addedSelectionCount = 0
+        editor.onDidAddSelection(() => { addedSelectionCount++ })
+
+        editor.addSelectionAbove()
+        editor.addSelectionAbove()
+        editor.addSelectionAbove()
+        expect(addedSelectionCount).toBe(3)
+      })
     })
 
     describe('.splitSelectionsIntoLines()', () => {
diff --git a/src/selection.js b/src/selection.js
index a15f6dcbd..2c64fa126 100644
--- a/src/selection.js
+++ b/src/selection.js
@@ -832,8 +832,12 @@ class Selection {
         if (clippedRange.isEmpty()) continue
       }
 
-      const selection = this.editor.addSelectionForScreenRange(clippedRange)
-      selection.setGoalScreenRange(range)
+      const containingSelections = this.editor.selectionsMarkerLayer.findMarkers({containsScreenRange: clippedRange})
+      if (containingSelections.length === 0) {
+        const selection = this.editor.addSelectionForScreenRange(clippedRange)
+        selection.setGoalScreenRange(range)
+      }
+
       break
     }
   }
@@ -854,8 +858,12 @@ class Selection {
         if (clippedRange.isEmpty()) continue
       }
 
-      const selection = this.editor.addSelectionForScreenRange(clippedRange)
-      selection.setGoalScreenRange(range)
+      const containingSelections = this.editor.selectionsMarkerLayer.findMarkers({containsScreenRange: clippedRange})
+      if (containingSelections.length === 0) {
+        const selection = this.editor.addSelectionForScreenRange(clippedRange)
+        selection.setGoalScreenRange(range)
+      }
+
       break
     }
   }