WIP: Reworking auto-indent/outdent logic

src/app/buffer.coffee

@@ -329,17 +329,27 @@ class Buffer
   isRowBlank: (row) ->
     not /\S/.test @lineForRow(row)
 
-  nextNonBlankRow: (row) ->
-    lastRow = @getLastRow()
-    if row < lastRow
-      for row in [(row + 1)..lastRow]
-        return row unless @isRowBlank(row)
+  previousNonBlankRow: (startRow) ->
+    startRow = Math.min(startRow, @getLastRow())
+    for row in [(startRow - 1)..0]
+      return row unless @isRowBlank(row)
+    null
 
+  nextNonBlankRow: (startRow) ->
+    lastRow = @getLastRow()
+    if startRow < lastRow
+      for row in [(startRow + 1)..lastRow]
+        return row unless @isRowBlank(row)
     null
 
   indentationForRow: (row) ->
     @lineForRow(row).match(/^\s*/)?[0].length
 
+  setIndentationForRow: (bufferRow, newLevel) ->
+    currentLevel = @indentationForRow(bufferRow)
+    indentString = [0...newLevel].map(-> ' ').join('')
+    @change([[bufferRow, 0], [bufferRow, currentLevel]], indentString)
+
   logLines: (start=0, end=@getLastRow())->
     for row in [start..end]
       line = @lineForRow(row)

src/app/edit-session.coffee

@@ -247,17 +247,17 @@ class EditSession
   largestFoldStartingAtScreenRow: (screenRow) ->
     @displayBuffer.largestFoldStartingAtScreenRow(screenRow)
 
-  indentationForRow: (row) ->
-    @languageMode.indentationForRow(row)
+  autoIndentBufferRows: (startRow, endRow) ->
+    @languageMode.autoIndentBufferRows(startRow, endRow)
 
-  autoIndentRows: (startRow, endRow) ->
-    @autoIndentRow(row) for row in [startRow..endRow]
+  autoIndentBufferRow: (bufferRow) ->
+    @languageMode.autoIndentBufferRow(bufferRow)
 
-  autoIndentRow: (row) ->
-    actualIndentation = @lineForBufferRow(row).match(/^\s*/)[0]
-    desiredIndentation = @indentationForRow(row)
-    if actualIndentation != desiredIndentation
-      @buffer.change([[row, 0], [row, actualIndentation.length]], desiredIndentation)
+  autoIncreaseIndentForBufferRow: (bufferRow) ->
+    @languageMode.autoIncreaseIndentForBufferRow(bufferRow)
+
+  autoDecreaseIndentForRow: (bufferRow) ->
+    @languageMode.autoDecreaseIndentForBufferRow(bufferRow)
 
   toggleLineCommentsInRange: (range) ->
     @languageMode.toggleLineCommentsInRange(range)

src/app/language-mode.coffee

@@ -13,7 +13,8 @@ class LanguageMode
     "'": "'"
 
   constructor: (@editSession) ->
-    @grammar = TextMateBundle.grammarForFileName(@editSession.buffer.getBaseName())
+    @buffer = @editSession.buffer
+    @grammar = TextMateBundle.grammarForFileName(@buffer.getBaseName())
 
     _.adviseBefore @editSession, 'insertText', (text) =>
       return true if @editSession.hasMultipleCursors()
@@ -84,25 +85,43 @@ class LanguageMode
 
     [bufferRow, foldEndRow]
 
-  indentationForRow: (row) ->
-    for precedingRow in [row - 1..-1]
-      return if precedingRow < 0
-      precedingLine = @editSession.buffer.lineForRow(precedingRow)
-      break if /\S/.test(precedingLine)
 
+  autoIndentBufferRows: (startRow, endRow) ->
+    @autoIndentBufferRow(row) for row in [startRow..endRow]
+
+  autoIndentBufferRow: (bufferRow) ->
+    @autoIncreaseIndentForBufferRow(bufferRow)
+    @autoDecreaseIndentForBufferRow(bufferRow)
+
+  autoIncreaseIndentForBufferRow: (bufferRow) ->
+    precedingRow = @buffer.previousNonBlankRow(bufferRow)
+    return unless precedingRow?
+
+    precedingLine = @editSession.lineForBufferRow(precedingRow)
     scopes = @tokenizedBuffer.scopesForPosition([precedingRow, Infinity])
-    indentation = precedingLine.match(/^\s*/)[0]
-    increaseIndentPattern = TextMateBundle.getPreferenceInScope(scopes[0], 'increaseIndentPattern')
-    decreaseIndentPattern = TextMateBundle.getPreferenceInScope(scopes[0], 'decreaseIndentPattern')
+    increaseIndentPattern = new OnigRegExp(TextMateBundle.getPreferenceInScope(scopes[0], 'increaseIndentPattern'))
 
-    if new OnigRegExp(increaseIndentPattern).search(precedingLine)
-      indentation += @editSession.tabText
+    currentIndentation = @buffer.indentationForRow(bufferRow)
+    desiredIndentation = @buffer.indentationForRow(precedingRow)
+    desiredIndentation += @editSession.tabText.length if increaseIndentPattern.test(precedingLine)
+    if desiredIndentation > currentIndentation
+      @buffer.setIndentationForRow(bufferRow, desiredIndentation)
 
-    line = @editSession.buffer.lineForRow(row)
-    if new OnigRegExp(decreaseIndentPattern).search(line)
-      indentation = indentation.replace(@editSession.tabText, "")
+  autoDecreaseIndentForBufferRow: (bufferRow) ->
+    scopes = @tokenizedBuffer.scopesForPosition([bufferRow, 0])
+    increaseIndentPattern = new OnigRegExp(TextMateBundle.getPreferenceInScope(scopes[0], 'increaseIndentPattern'))
+    decreaseIndentPattern = new OnigRegExp(TextMateBundle.getPreferenceInScope(scopes[0], 'decreaseIndentPattern'))
+    line = @buffer.lineForRow(bufferRow)
+    return unless decreaseIndentPattern.test(line)
 
-    indentation
+    currentIndentation = @buffer.indentationForRow(bufferRow)
+    precedingRow = @buffer.previousNonBlankRow(bufferRow)
+    precedingLine = @buffer.lineForRow(precedingRow)
+
+    desiredIndentation = @buffer.indentationForRow(precedingRow)
+    desiredIndentation -= @editSession.tabText.length unless increaseIndentPattern.test(precedingLine)
+    if desiredIndentation < currentIndentation
+      @buffer.setIndentationForRow(bufferRow, desiredIndentation)
 
   getLineTokens: (line, stack) ->
     {tokens, stack} = @grammar.getLineTokens(line, stack)

src/app/range.coffee

@@ -74,3 +74,6 @@ class Range
     else
       columns = @end.column
     new Point(rows, columns)
+
+  getRowCount: ->
+    @end.row - @start.row + 1

src/app/selection.coffee

@@ -134,7 +134,18 @@ class Selection
     @cursor.setBufferPosition(newBufferRange.end, skipAtomicTokens: true) if wasReversed
 
     if @editSession.autoIndent
-      @editSession.autoIndentRows(newBufferRange.start.row, newBufferRange.end.row)
+      if /\n/.test(text)
+        firstLinePrefix = @editSession.getTextInBufferRange([[newBufferRange.start.row, 0], newBufferRange.start])
+        if /^\s*$/.test(firstLinePrefix)
+          @editSession.autoIncreaseIndentForBufferRow(newBufferRange.start.row)
+          if newBufferRange.getRowCount() > 1
+            @editSession.autoIndentBufferRows(newBufferRange.start.row + 1, newBufferRange.end.row)
+        else
+          @editSession.autoIncreaseIndentForBufferRow(newBufferRange.start.row + 1)
+          if newBufferRange.getRowCount() > 2
+            @editSession.autoIndentBufferRows(newBufferRange.start.row + 2, newBufferRange.end.row)
+      else
+        @editSession.autoDecreaseIndentForRow(newBufferRange.start.row)
 
   backspace: ->
     if @isEmpty() and not @editSession.isFoldedAtScreenRow(@cursor.getScreenRow())