DevTools: edit SASS through SourceMaps.

Source/devtools/front_end/bindings/SASSStructureMapping.js

Index: Source/devtools/front_end/bindings/SASSStructureMapping.js
diff --git a/Source/devtools/front_end/bindings/SASSStructureMapping.js b/Source/devtools/front_end/bindings/SASSStructureMapping.js
new file mode 100644
index 0000000000000000000000000000000000000000..593a9667492e0ad39147dd5cd4b9d7ab60b8fa60
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+++ b/Source/devtools/front_end/bindings/SASSStructureMapping.js
@@ -0,0 +1,301 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @constructor
+ * @param {!Map<string, string>} sassSources
+ */
+WebInspector.SASSStructureMapping = function(cssStruct, sassSources)
+{
+    this._sources = sassSources;
+    this._cssStruct = cssStruct;
+    this._sassStructs = new Map();
+}
+
+WebInspector.SASSStructureMapping.prototype = {
+    cssPropertyValueToSASS: function(cssValueRange, sourceMap)
+    {
+        var entry = sourceMap.findEntry(cssValueRange.endLine, cssValueRange.endColumn);
+        var url = entry.sourceURL;
+        var struct = this._structForURL(url);
+        if (!struct) {
+            console.error("Failed to get structure of " + url);
+            return null;
+        }
+        var sassValue = this._sassValue(struct, entry);
+        if (!sassValue)
+            return null;
+        return {
+            url: url,
+            range: sassValue.range
+        };
+    },
+
+    cssPropertyToSASS: function(cssPropertyRange, sourceMap)
+    {
+        var entry = sourceMap.findEntry(cssPropertyRange.startLine, cssPropertyRange.startColumn);
+        var struct = this._structForURL(entry.sourceURL);
+        if (!struct) {
+            console.error("Failed to get structure of " + entry.sourceURL);
+            return null;
+        }
+        var sassProperty = this._sassProperty(struct, entry);
+        if (!sassProperty)
+            return null;
+        return {
+            url: entry.sourceURL,
+            range: sassProperty.range
+        };
+    },
+
+    sassPropertyValueToCSS: function(sassURL, sassValueRange, sourceMap)
+    {
+        var reversedEntries = sourceMap.findEntriesReversed(sassURL, sassValueRange.endLine, sassValueRange.endColumn - 1);
+        var result = [];
+        for (var i = 0; i < reversedEntries.length; ++i) {
+            var value = this._cssValue(reversedEntries[i]);
+            console.assert(value, "Failed to find reversed mapped property value.");
+            result.push(value);
+        }
+        return result;
+    },
+
+    _sassProperty: function(struct, entry)
+    {
+        for (var i = 0; i < struct.properties.length; ++i) {
+            var property = struct.properties[i];
+            if (this._rangeContainsSourceMapping(property.range, entry))
+                return property;
+        }
+        return null;
+    },
+
+    _sassVariable: function(struct, entry)
+    {
+        for (var i = 0; i < struct.variables.length; ++i) {
+            var variable = struct.variables[i];
+            if (this._rangeContainsSourceMapping(variable.range, entry))
+                return variable;
+        }
+        return null;
+    },
+
+    _sassValue: function(struct, entry)
+    {
+        var sassProperty = this._sassProperty(struct, entry);
+        if (sassProperty && this._rangeContainsSourceMapping(sassProperty.value.range, entry))
+            return sassProperty.value;
+
+        var sassVariable = this._sassVariable(struct, entry);
+        if (sassVariable && this._rangeContainsSourceMapping(sassVariable.value.range, entry))
+            return sassVariable.value;
+        for (var i = 0; i < struct.mixinValues.length; ++i) {
+            var mixinValue = struct.mixinValues[i];
+            if (this._rangeContainsSourceMapping(mixinValue.range, entry))
+                return mixinValue;
+        }
+        return null;
+    },
+
+    _cssProperty: function(entry)
+    {
+        for (var i = 0; i < this._cssStruct.length; ++i) {
+            var rule = this._cssStruct[i];
+            for (var j = 0; j < rule.properties.length; ++j) {
+                var property = rule.properties[j];
+                if (this._rangeContainsCompiledMapping(property.range, entry))
+                    return property;
+            }
+        }
+        return null;
+    },
+
+    _cssValue: function(entry)
+    {
+        var cssProperty = this._cssProperty(entry);
+        if (cssProperty && this._rangeContainsCompiledMapping(cssProperty.valueRange, entry))
+            return cssProperty;
+        return null;
+    },
+
+    _rangeContainsSourceMapping: function(range, entry)
+    {
+        if (range.startLine === range.endLine)
+            return range.startLine === entry.sourceLineNumber && range.startColumn <= entry.sourceColumnNumber && entry.sourceColumnNumber <= range.endColumn;
+        if (range.startLine === entry.sourceLineNumber)
+            return range.startColumn <= entry.sourceColumnNumber;
+        if (range.endLine === entry.sourceLineNumber)
+            return entry.sourceColumnNumber <= range.endColumn;
+        return range.startLine < entry.sourceLineNumber && entry.sourceLineNumber < range.endLine;
+    },
+
+    _rangeContainsCompiledMapping: function(range, entry)
+    {
+        if (range.startLine === range.endLine)
+            return range.startLine === entry.lineNumber && range.startColumn <= entry.columnNumber && entry.columnNumber <= range.endColumn;
+        if (range.startLine === entry.lineNumber)
+            return range.startColumn <= entry.columnNumber;
+        if (range.endLine === entry.lineNumber)
+            return entry.columnNumber <= range.endColumn;
+        return range.startLine < entry.lineNumber && entry.lineNumber < range.endLine;
+    },
+
+    _structForURL: function(sassURL)
+    {
+        if (this._sassStructs.has(sassURL))
+            return this._sassStructs.get(sassURL);
+        var source = this._sources.get(sassURL);
+        if (!source)
+            return null;
+        var result = WebInspector.SASSStructureMapping.parseSASS(source);
+        this._sassStructs.set(sassURL, result);
+        return result;
+    }
+}
+
+
+WebInspector.SASSStructureMapping.SCSSParserStates = {
+    Initial: "Initial",
+    PropertyName: "PropertyName",
+    PropertyValue: "PropertyValue",
+    VariableName: "VariableName",
+    VariableValue: "VariableValue",
+    MixinInclude: "MixinInclude",
+    MixinValue: "MixinValue"
+}
+
+WebInspector.SASSStructureMapping.parseSASS = function(text)
+{
+    var lines = text.split("\n");
+    var properties = [];
+    var variables = [];
+    var mixinValues = [];
+
+    var States = WebInspector.SASSStructureMapping.SCSSParserStates;
+    var state = States.Initial;
+    var property;
+    var variable;
+    var mixin;
+    var UndefTokenType = {};
+
+    /**
+     * @param {string} tokenValue
+     * @param {?string} tokenTypes
+     * @param {number} column
+     * @param {number} newColumn
+     */
+    function processToken(tokenValue, tokenTypes, column, newColumn)
+    {
+        var tokenType = tokenTypes ? tokenTypes.split(" ").keySet() : UndefTokenType;
+        switch (state) {
+        case States.Initial:
+            if (tokenType["css-variable-2"]) {
+                variable = {
+                    name: {
+                        content: tokenValue,
+                        range: new WebInspector.TextRange(lineNumber, column, lineNumber, newColumn)
+                    },
+                    value: {
+                        content: "",
+                    },
+                    range: WebInspector.TextRange.createFromLocation(lineNumber, column)
+                }
+                state = States.VariableName;
+            } else if (tokenType["css-property"] || tokenType["css-meta"]) {
+                property = {
+                    name: {
+                        content: tokenValue,
+                        range: new WebInspector.TextRange(lineNumber, column, lineNumber, newColumn)
+                    },
+                    value: {
+                        content: "",
+                    },
+                    range: WebInspector.TextRange.createFromLocation(lineNumber, column)
+                }
+                state = States.PropertyName;
+            } else if (tokenType["css-def"] && tokenValue === "@include") {
+                state = States.MixinInclude;
+            }
+            break;
+        case States.VariableName:
+            if (tokenValue === ")" && tokenType === UndefTokenType) {
+                state = States.Initial;
+            } else if (tokenValue === ":" && tokenType === UndefTokenType) {
+                state = States.VariableValue;
+                variable.value.range = WebInspector.TextRange.createFromLocation(lineNumber, newColumn);
+            } else if (tokenType !== UndefTokenType) {
+                state = States.Initial;
+            }
+            break;
+        case States.VariableValue:
+            if (tokenValue === ";" && tokenType === UndefTokenType) {
+                variable.value.range.endLine = lineNumber;
+                variable.value.range.endColumn = column;
+                variable.range.endLine = lineNumber;
+                variable.range.endColumn = newColumn;
+                variables.push(variable);
+                state = States.Initial;
+            } else {
+                variable.value.content += tokenValue;
+            }
+            break;
+        case States.PropertyName:
+            if (tokenValue === ":" && tokenType === UndefTokenType) {
+                state = States.PropertyValue;
+                property.value.range = WebInspector.TextRange.createFromLocation(lineNumber, newColumn);
+            } else if (tokenType["property"]) {
+                property.name.contet += tokenValue;
+            }
+            break;
+        case States.PropertyValue:
+            if (tokenValue === ";" && tokenType === UndefTokenType) {
+                property.value.range.endLine = lineNumber;
+                property.value.range.endColumn = column;
+                property.range.endLine = lineNumber;
+                property.range.endColumn = newColumn;
+                properties.push(property);
+                state = States.Initial;
+            } else {
+                property.value.content += tokenValue;
+            }
+            break;
+        case States.MixinInclude:
+            if (tokenValue === "(" && tokenType === UndefTokenType) {
+                state = States.MixinValue;
+                mixin = {
+                    range: WebInspector.TextRange.createFromLocation(lineNumber, newColumn),
+                    value: ""
+                };
+            } else if (tokenValue === ";" && tokenType === UndefTokenType) {
+                state = States.Initial;
+                if (mixin)
+                    mixinValues.push(mixin);
+                mixin = null;
+            }
+            break;
+        case States.MixinValue:
+            if (tokenValue === ")" && tokenType === UndefTokenType) {
+                state = States.MixinInclude;
+                mixin.range.endLine = lineNumber;
+                mixin.range.endColumn = column;
+            } else {
+                mixin.value += tokenValue;
+            }
+            break;
+        default:
+            console.assert(false, "Unknown CSS parser state.");
+        }
+    }
+    var tokenizer = new WebInspector.CodeMirrorUtils.TokenizerFactory().createTokenizer("text/x-scss");
+    var lineNumber;
+    for (lineNumber = 0; lineNumber < lines.length; ++lineNumber) {
+        var line = lines[lineNumber];
+        tokenizer(line, processToken);
+    }
+    return {
+        variables: variables,
+        properties: properties,
+        mixinValues: mixinValues
+    };
+}