[powershell mode] Improve

corrected angle bracket matching in operators (fixes block comments)
corrected digit matching regex
corrected spelling of 'identifier' in grammar dictionary
notCharacterOrDash explicitly includes lowercase characters
improved variable matching
splatted variables now match
bare '$' and '@' are errors, not variables
moved single-quoted string processing into tokenSingleQuoteString
incomplete strings are errors now
empty strings are no longer errors
added support for here-string interpolation with nesting support
added highlighting for splatted vars
removed arbitrary stream advancement prior to default error in tokenBase
enabled folding braces

Author: benmiller-google

mode/powershell/powershell.js

@@ -1,6 +1,9 @@
-// Initially based on CodeMirror Python mode, copyright (c) by Marijn Haverbeke and others
-// PowerShell mode, copyright (c) Andrey Shchekin, VapidWorx and others
-// Distributed under an MIT license: http://codemirror.net/LICENSE
+/**
+ * @license
+ * Initially based on CodeMirror Python mode, copyright (c) by Marijn Haverbeke and others
+ * PowerShell mode, copyright (c) Andrey Shchekin, VapidWorx and others
+ * Distributed under an MIT license: http://codemirror.net/LICENSE
+ */
 
 (function(mod) {
   'use strict';
@@ -31,7 +34,8 @@ CodeMirror.defineMode('powershell', function() {
         return new RegExp(prefix + '(' + patterns.join('|') + ')' + suffix, 'i');
     }
 
-    var notCharacterOrDash = '(?=[^A-Z\\d\\-_]|$)';
+    var notCharacterOrDash = '(?=[^A-Za-z\\d\\-_]|$)';
+    var varNames = /[\w\-:]/
     var keywords = buildRegexp([
         /begin|break|catch|continue|data|default|do|dynamicparam/,
         /else|elseif|end|exit|filter|finally|for|foreach|from|function|if|in/,
@@ -49,10 +53,10 @@ CodeMirror.defineMode('powershell', function() {
         /[ic]?replace/,
         /b?(and|or|xor)/
     ], { prefix: '-' });
-    var symbolOperators = /[+\-*\/%]=|\+\+|--|\.\.|[+\-*&^%:=<>!|\/]/;
+    var symbolOperators = /[+\-*\/%]=|\+\+|--|\.\.|[+\-*&^%:=!|\/]|<(?!#)|(?!#)>/;
     var operators = buildRegexp([wordOperators, symbolOperators], { suffix: '' });
 
-    var numbers = /^[+-]?(0x[\da-f]+|(\d+(\.\d+)?|\.\d*)(e[\+\-]?\d+)?)[ld]?([kmgtp]b)?/i;
+    var numbers = /^[+-]?((0x[\da-f]+)|((\d+\.\d+|\d\.|\.\d+|\d+)(e[\+\-]?\d+)?))[ld]?([kmgtp]b)?/i;
 
     var identifiers = /^[A-Za-z\_][A-Za-z\-\_\d]*\b/;
 
@@ -106,8 +110,8 @@ CodeMirror.defineMode('powershell', function() {
         /Save-Help/,
         /Select-(Object|String|Xml)/,
         /Send-MailMessage/,
-        new RegExp('Set-(Acl|Alias|AuthenticodeSignature|Content|Date|ExecutionPolicy|Item(Property)?|Location|PSBreakpoint|PSDebug'
-          + '|PSSessionConfiguration|Service|StrictMode|TraceSource|Variable|WmiInstance)'),
+        new RegExp('Set-(Acl|Alias|AuthenticodeSignature|Content|Date|ExecutionPolicy|Item(Property)?|Location|PSBreakpoint|PSDebug' +
+                   '|PSSessionConfiguration|Service|StrictMode|TraceSource|Variable|WmiInstance)'),
         /Show-(Command|ControlPanelItem|EventLog)/,
         /Sort-Object/,
         /Split-Path/,
@@ -132,7 +136,7 @@ CodeMirror.defineMode('powershell', function() {
         /group|gsn|gsnp|gsv|gu|gv|gwmi|h|history|icm|iex|ihy|ii|ipal|ipcsv|ipmo|ipsn|irm|ise|iwmi|iwr|kill|lp|ls|man|md/,
         /measure|mi|mount|move|mp|mv|nal|ndr|ni|nmo|npssc|nsn|nv|ogv|oh|popd|ps|pushd|pwd|r|rbp|rcjb|rcsn|rd|rdr|ren|ri/,
         /rjb|rm|rmdir|rmo|rni|rnp|rp|rsn|rsnp|rujb|rv|rvpa|rwmi|sajb|sal|saps|sasv|sbp|sc|select|set|shcm|si|sl|sleep|sls/,
-        /sort|sp|spjb|spps|spsv|start|sujb|sv|swmi|tee|trcm|type|where|wjb|write/,
+        /sort|sp|spjb|spps|spsv|start|sujb|sv|swmi|tee|trcm|type|where|wjb|write/
     ], { prefix: '', suffix: '' });
     var variableBuiltins = buildRegexp([
         /[$?^_]|Args|ConfirmPreference|ConsoleFileName|DebugPreference|Error|ErrorActionPreference|ErrorView|ExecutionContext/,
@@ -147,15 +151,15 @@ CodeMirror.defineMode('powershell', function() {
         /true|false|null/
     ], { prefix: '\\$', suffix: '' });
 
-    var builtins = buildRegexp([ symbolBuiltins, namedBuiltins, variableBuiltins ], { suffix: notCharacterOrDash });
+    var builtins = buildRegexp([symbolBuiltins, namedBuiltins, variableBuiltins], { suffix: notCharacterOrDash });
 
     var grammar = {
         keyword: keywords,
         number: numbers,
         operator: operators,
         builtin: builtins,
         punctuation: punctuation,
-        indetifier: identifiers
+        identifier: identifiers
     };
 
     // tokenizers
@@ -190,12 +194,13 @@ CodeMirror.defineMode('powershell', function() {
             }
         }
 
+        var ch = stream.next();
+
         // single-quote string
-        if (stream.match(/'([^']|'')+'/)) {
-            return 'string';
+        if (ch === "'") {
+            return tokenSingleQuoteString(stream, state);
         }
 
-        var ch = stream.next();
         if (ch === '$') {
             return tokenVariable(stream, state);
         }
@@ -221,18 +226,35 @@ CodeMirror.defineMode('powershell', function() {
                 state.tokenize = tokenMultiString;
                 state.startQuote = quoteMatch[0];
                 return tokenMultiString(stream, state);
+            } else if (stream.peek().match(/[({]/)) {
+                return 'punctuation';
+            } else if (stream.match(varNames)) {
+              // splatted variable
+              return tokenVariable(stream, state);
+            }
+        }
+        return 'error';
+    }
+
+    function tokenSingleQuoteString(stream, state) {
+        var ch;
+        while ((ch = stream.peek()) != null) {
+            stream.next();
+
+            if (ch === "'" && !stream.eat("'")) {
+                state.tokenize = tokenBase;
+                return 'string';
             }
         }
 
-        stream.next();
         return 'error';
     }
 
     function tokenDoubleQuoteString(stream, state) {
         var ch;
-        while((ch = stream.peek()) != null) {
+        while ((ch = stream.peek()) != null) {
             if (ch === '$') {
-                state.tokenize = tokenInterpolation;
+                state.tokenize = tokenStringInterpolation;
                 return 'string';
             }
 
@@ -251,15 +273,30 @@ CodeMirror.defineMode('powershell', function() {
         return 'error';
     }
 
-    function tokenInterpolation(stream, state) {
+    function tokenStringInterpolation(stream, state) {
+        return tokenInterpolation(stream, state, tokenDoubleQuoteString);
+    }
+
+    function tokenMultiStringReturn(stream, state) {
+        state.tokenize = tokenMultiString;
+        state.startQuote = '"'
+        return tokenMultiString(stream, state);
+    }
+
+    function tokenHereStringInterpolation(stream, state) {
+        var saved;
+        return tokenInterpolation(stream, state, tokenMultiStringReturn);
+    }
+
+    function tokenInterpolation(stream, state, parentTokenize) {
         if (stream.match('$(')) {
             var savedBracketNesting = state.bracketNesting;
             state.returnStack.push({
                 /*jshint loopfunc:true */
                 shouldReturnFrom: function(state) {
                     return state.bracketNesting === savedBracketNesting;
                 },
-                tokenize: tokenDoubleQuoteString
+                tokenize: parentTokenize
             });
             state.tokenize = tokenBase;
             state.bracketNesting += 1;
@@ -268,7 +305,7 @@ CodeMirror.defineMode('powershell', function() {
             stream.next();
             state.returnStack.push({
                 shouldReturnFrom: function() { return true; },
-                tokenize: tokenDoubleQuoteString
+                tokenize: parentTokenize
             });
             state.tokenize = tokenVariable;
             return state.tokenize(stream, state);
@@ -288,13 +325,17 @@ CodeMirror.defineMode('powershell', function() {
     }
 
     function tokenVariable(stream, state) {
+        var ch = stream.peek();
         if (stream.eat('{')) {
             state.tokenize = tokenVariableWithBraces;
             return tokenVariableWithBraces(stream, state);
-        } else {
-            stream.eatWhile(/[\w\\\-:]/);
+        } else if (ch != undefined && ch.match(varNames)) {
+            stream.eatWhile(varNames);
             state.tokenize = tokenBase;
             return 'variable-2';
+        } else {
+            state.tokenize = tokenBase;
+            return 'error';
         }
     }
 
@@ -314,6 +355,20 @@ CodeMirror.defineMode('powershell', function() {
         if (stream.sol() && stream.match(new RegExp(quote + '@'))) {
             state.tokenize = tokenBase;
         }
+        else if (quote === '"') {
+            while (!stream.eol()) {
+                var ch = stream.peek();
+                if (ch === '$') {
+                    state.tokenize = tokenHereStringInterpolation;
+                    return 'string';
+                }
+
+                stream.next();
+                if (ch === '`') {
+                    stream.next();
+                }
+            }
+        }
         else {
             stream.skipToEnd();
         }
@@ -336,10 +391,11 @@ CodeMirror.defineMode('powershell', function() {
 
         blockCommentStart: '<#',
         blockCommentEnd: '#>',
-        lineComment: '#'
+        lineComment: '#',
+        fold: 'brace'
     };
     return external;
 });
 
 CodeMirror.defineMIME('text/x-powershell', 'powershell');
-});
+});