Add initial support for injection grammars

Build scope selectors and patterns when setting up the grammar
for all entries under the grammar's injection object.

Include the injection patterns in the scanner when the injection's
scope selector matches the current rule stack.

src/app/text-mate-grammar.coffee

@@ -5,6 +5,7 @@ Token = require 'token'
 {OnigRegExp, OnigScanner} = require 'oniguruma'
 nodePath = require 'path'
 pathSplitRegex = new RegExp("[#{nodePath.sep}.]")
+TextMateScopeSelector = require 'text-mate-scope-selector'
 
 ###
 # Internal #
@@ -33,8 +34,9 @@ class TextMateGrammar
   firstLineRegex: null
   maxTokensPerLine: 100
 
-  constructor: ({ @name, @fileTypes, @scopeName, patterns, repository, @foldingStopMarker, firstLineMatch}) ->
-    @initialRule = new Rule(this, {@scopeName, patterns})
+  constructor: ({ @name, @fileTypes, @scopeName, injections, patterns, repository, @foldingStopMarker, firstLineMatch}) ->
+    injections = @parseInjections(injections)
+    @initialRule = new Rule(this, {@scopeName, patterns, injections})
     @repository = {}
     @firstLineRegex = new OnigRegExp(firstLineMatch) if firstLineMatch
     @fileTypes ?= []
@@ -43,6 +45,18 @@ class TextMateGrammar
       data = {patterns: [data], tempName: name} if data.begin? or data.match?
       @repository[name] = new Rule(this, data)
 
+  parseInjections: (injections={}) ->
+    parsedInjections = []
+    for injectionKey, injectionValue of injections
+      continue unless injectionValue?.patterns?.length > 0
+      injectionPatterns = []
+      for pattern in injectionValue.patterns
+        injectionPatterns.push(new Pattern(this, pattern))
+      parsedInjections.push
+        patterns: injectionPatterns
+        matcher: new TextMateScopeSelector(injectionKey)
+    parsedInjections
+
   getScore: (path, contents) ->
     contents = fsUtils.read(path) if not contents? and fsUtils.isFile(path)
 
@@ -140,8 +154,9 @@ class Rule
   createEndPattern: null
   anchorPosition: -1
 
-  constructor: (@grammar, {@scopeName, patterns, @endPattern}) ->
+  constructor: (@grammar, {@scopeName, patterns, injections, @endPattern}) ->
     patterns ?= []
+    @injections = injections ? []
     @patterns = patterns.map (pattern) => new Pattern(grammar, pattern)
     @patterns.unshift(@endPattern) if @endPattern and !@endPattern.hasBackReferences
     @scannersByBaseGrammarName = {}
@@ -157,12 +172,19 @@ class Rule
 
   clearAnchorPosition: -> @anchorPosition = -1
 
-  getScanner: (baseGrammar, position, firstLine) ->
+  getScanner: (ruleStack, baseGrammar, position, firstLine) ->
     return scanner if scanner = @scannersByBaseGrammarName[baseGrammar.name]
 
     anchored = false
+    injected = true
     regexes = []
     patterns = @getIncludedPatterns(baseGrammar)
+    scopes = scopesFromStack(ruleStack)
+    for injection in @injections
+      if injection.matcher.matches(scopes)
+        patterns.push(injection.patterns...)
+        injected = true
+
     patterns.forEach (pattern) =>
       if pattern.anchored
         anchored = true
@@ -173,14 +195,14 @@ class Rule
 
     regexScanner = new OnigScanner(regexes)
     regexScanner.patterns = patterns
-    @scannersByBaseGrammarName[baseGrammar.name] = regexScanner unless anchored
+    unless anchored or injected
+      @scannersByBaseGrammarName[baseGrammar.name] = regexScanner
     regexScanner
 
   getNextTokens: (ruleStack, line, position, firstLine) ->
     baseGrammar = ruleStack[0].grammar
-    patterns = @getIncludedPatterns(baseGrammar)
 
-    scanner = @getScanner(baseGrammar, position, firstLine)
+    scanner = @getScanner(ruleStack, baseGrammar, position, firstLine)
     # Add a `\n` to appease patterns that contain '\n' explicitly
     return null unless result = scanner.findNextMatch("#{line}\n", position)
     { index, captureIndices } = result
@@ -191,7 +213,7 @@ class Rule
       value
 
     [firstCaptureIndex, firstCaptureStart, firstCaptureEnd] = captureIndices
-    nextTokens = patterns[index].handleMatch(ruleStack, line, captureIndices)
+    nextTokens = scanner.patterns[index].handleMatch(ruleStack, line, captureIndices)
     { nextTokens, tokensStartPosition: firstCaptureStart, tokensEndPosition: firstCaptureEnd }
 
   getRuleToPush: (line, beginPatternCaptureIndices) ->