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-rw-r--r--devtools/shared/inspector/css-logic.js325
-rw-r--r--devtools/shared/inspector/moz.build9
2 files changed, 334 insertions, 0 deletions
diff --git a/devtools/shared/inspector/css-logic.js b/devtools/shared/inspector/css-logic.js
new file mode 100644
index 000000000..c8cdd2fdb
--- /dev/null
+++ b/devtools/shared/inspector/css-logic.js
@@ -0,0 +1,325 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * About the objects defined in this file:
+ * - CssLogic contains style information about a view context. It provides
+ * access to 2 sets of objects: Css[Sheet|Rule|Selector] provide access to
+ * information that does not change when the selected element changes while
+ * Css[Property|Selector]Info provide information that is dependent on the
+ * selected element.
+ * Its key methods are highlight(), getPropertyInfo() and forEachSheet(), etc
+ * It also contains a number of static methods for l10n, naming, etc
+ *
+ * - CssSheet provides a more useful API to a DOM CSSSheet for our purposes,
+ * including shortSource and href.
+ * - CssRule a more useful API to a nsIDOMCSSRule including access to the group
+ * of CssSelectors that the rule provides properties for
+ * - CssSelector A single selector - i.e. not a selector group. In other words
+ * a CssSelector does not contain ','. This terminology is different from the
+ * standard DOM API, but more inline with the definition in the spec.
+ *
+ * - CssPropertyInfo contains style information for a single property for the
+ * highlighted element.
+ * - CssSelectorInfo is a wrapper around CssSelector, which adds sorting with
+ * reference to the selected element.
+ */
+
+"use strict";
+
+/**
+ * Provide access to the style information in a page.
+ * CssLogic uses the standard DOM API, and the Gecko inIDOMUtils API to access
+ * styling information in the page, and present this to the user in a way that
+ * helps them understand:
+ * - why their expectations may not have been fulfilled
+ * - how browsers process CSS
+ * @constructor
+ */
+
+const Services = require("Services");
+const CSSLexer = require("devtools/shared/css/lexer");
+const {LocalizationHelper} = require("devtools/shared/l10n");
+const styleInspectorL10N =
+ new LocalizationHelper("devtools/shared/locales/styleinspector.properties");
+
+/**
+ * Special values for filter, in addition to an href these values can be used
+ */
+exports.FILTER = {
+ // show properties for all user style sheets.
+ USER: "user",
+ // USER, plus user-agent (i.e. browser) style sheets
+ UA: "ua",
+};
+
+/**
+ * Each rule has a status, the bigger the number, the better placed it is to
+ * provide styling information.
+ *
+ * These statuses are localized inside the styleinspector.properties
+ * string bundle.
+ * @see csshtmltree.js RuleView._cacheStatusNames()
+ */
+exports.STATUS = {
+ BEST: 3,
+ MATCHED: 2,
+ PARENT_MATCH: 1,
+ UNMATCHED: 0,
+ UNKNOWN: -1,
+};
+
+/**
+ * Lookup a l10n string in the shared styleinspector string bundle.
+ *
+ * @param {String} name
+ * The key to lookup.
+ * @returns {String} A localized version of the given key.
+ */
+exports.l10n = name => styleInspectorL10N.getStr(name);
+
+/**
+ * Is the given property sheet a content stylesheet?
+ *
+ * @param {CSSStyleSheet} sheet a stylesheet
+ * @return {boolean} true if the given stylesheet is a content stylesheet,
+ * false otherwise.
+ */
+exports.isContentStylesheet = function (sheet) {
+ return sheet.parsingMode !== "agent";
+};
+
+/**
+ * Return a shortened version of a style sheet's source.
+ *
+ * @param {CSSStyleSheet} sheet the DOM object for the style sheet.
+ */
+exports.shortSource = function (sheet) {
+ // Use a string like "inline" if there is no source href
+ if (!sheet || !sheet.href) {
+ return exports.l10n("rule.sourceInline");
+ }
+
+ // We try, in turn, the filename, filePath, query string, whole thing
+ let url = {};
+ try {
+ url = new URL(sheet.href);
+ } catch (ex) {
+ // Some UA-provided stylesheets are not valid URLs.
+ }
+
+ if (url.pathname) {
+ let index = url.pathname.lastIndexOf("/");
+ if (index !== -1 && index < url.pathname.length) {
+ return url.pathname.slice(index + 1);
+ }
+ return url.pathname;
+ }
+
+ if (url.query) {
+ return url.query;
+ }
+
+ let dataUrl = sheet.href.match(/^(data:[^,]*),/);
+ return dataUrl ? dataUrl[1] : sheet.href;
+};
+
+const TAB_CHARS = "\t";
+
+/**
+ * Prettify minified CSS text.
+ * This prettifies CSS code where there is no indentation in usual places while
+ * keeping original indentation as-is elsewhere.
+ * @param string text The CSS source to prettify.
+ * @return string Prettified CSS source
+ */
+function prettifyCSS(text, ruleCount) {
+ if (prettifyCSS.LINE_SEPARATOR == null) {
+ let os = Services.appinfo.OS;
+ prettifyCSS.LINE_SEPARATOR = (os === "WINNT" ? "\r\n" : "\n");
+ }
+
+ // remove initial and terminating HTML comments and surrounding whitespace
+ text = text.replace(/(?:^\s*<!--[\r\n]*)|(?:\s*-->\s*$)/g, "");
+ let originalText = text;
+ text = text.trim();
+
+ // don't attempt to prettify if there's more than one line per rule.
+ let lineCount = text.split("\n").length - 1;
+ if (ruleCount !== null && lineCount >= ruleCount) {
+ return originalText;
+ }
+
+ // We reformat the text using a simple state machine. The
+ // reformatting preserves most of the input text, changing only
+ // whitespace. The rules are:
+ //
+ // * After a "{" or ";" symbol, ensure there is a newline and
+ // indentation before the next non-comment, non-whitespace token.
+ // * Additionally after a "{" symbol, increase the indentation.
+ // * A "}" symbol ensures there is a preceding newline, and
+ // decreases the indentation level.
+ // * Ensure there is whitespace before a "{".
+ //
+ // This approach can be confused sometimes, but should do ok on a
+ // minified file.
+ let indent = "";
+ let indentLevel = 0;
+ let tokens = CSSLexer.getCSSLexer(text);
+ let result = "";
+ let pushbackToken = undefined;
+
+ // A helper function that reads tokens, looking for the next
+ // non-comment, non-whitespace token. Comment and whitespace tokens
+ // are appended to |result|. If this encounters EOF, it returns
+ // null. Otherwise it returns the last whitespace token that was
+ // seen. This function also updates |pushbackToken|.
+ let readUntilSignificantToken = () => {
+ while (true) {
+ let token = tokens.nextToken();
+ if (!token || token.tokenType !== "whitespace") {
+ pushbackToken = token;
+ return token;
+ }
+ // Saw whitespace. Before committing to it, check the next
+ // token.
+ let nextToken = tokens.nextToken();
+ if (!nextToken || nextToken.tokenType !== "comment") {
+ pushbackToken = nextToken;
+ return token;
+ }
+ // Saw whitespace + comment. Update the result and continue.
+ result = result + text.substring(token.startOffset, nextToken.endOffset);
+ }
+ };
+
+ // State variables for readUntilNewlineNeeded.
+ //
+ // Starting index of the accumulated tokens.
+ let startIndex;
+ // Ending index of the accumulated tokens.
+ let endIndex;
+ // True if any non-whitespace token was seen.
+ let anyNonWS;
+ // True if the terminating token is "}".
+ let isCloseBrace;
+ // True if the token just before the terminating token was
+ // whitespace.
+ let lastWasWS;
+
+ // A helper function that reads tokens until there is a reason to
+ // insert a newline. This updates the state variables as needed.
+ // If this encounters EOF, it returns null. Otherwise it returns
+ // the final token read. Note that if the returned token is "{",
+ // then it will not be included in the computed start/end token
+ // range. This is used to handle whitespace insertion before a "{".
+ let readUntilNewlineNeeded = () => {
+ let token;
+ while (true) {
+ if (pushbackToken) {
+ token = pushbackToken;
+ pushbackToken = undefined;
+ } else {
+ token = tokens.nextToken();
+ }
+ if (!token) {
+ endIndex = text.length;
+ break;
+ }
+
+ // A "}" symbol must be inserted later, to deal with indentation
+ // and newline.
+ if (token.tokenType === "symbol" && token.text === "}") {
+ isCloseBrace = true;
+ break;
+ } else if (token.tokenType === "symbol" && token.text === "{") {
+ break;
+ }
+
+ if (token.tokenType !== "whitespace") {
+ anyNonWS = true;
+ }
+
+ if (startIndex === undefined) {
+ startIndex = token.startOffset;
+ }
+ endIndex = token.endOffset;
+
+ if (token.tokenType === "symbol" && token.text === ";") {
+ break;
+ }
+
+ lastWasWS = token.tokenType === "whitespace";
+ }
+ return token;
+ };
+
+ while (true) {
+ // Set the initial state.
+ startIndex = undefined;
+ endIndex = undefined;
+ anyNonWS = false;
+ isCloseBrace = false;
+ lastWasWS = false;
+
+ // Read tokens until we see a reason to insert a newline.
+ let token = readUntilNewlineNeeded();
+
+ // Append any saved up text to the result, applying indentation.
+ if (startIndex !== undefined) {
+ if (isCloseBrace && !anyNonWS) {
+ // If we saw only whitespace followed by a "}", then we don't
+ // need anything here.
+ } else {
+ result = result + indent + text.substring(startIndex, endIndex);
+ if (isCloseBrace) {
+ result += prettifyCSS.LINE_SEPARATOR;
+ }
+ }
+ }
+
+ if (isCloseBrace) {
+ indent = TAB_CHARS.repeat(--indentLevel);
+ result = result + indent + "}";
+ }
+
+ if (!token) {
+ break;
+ }
+
+ if (token.tokenType === "symbol" && token.text === "{") {
+ if (!lastWasWS) {
+ result += " ";
+ }
+ result += "{";
+ indent = TAB_CHARS.repeat(++indentLevel);
+ }
+
+ // Now it is time to insert a newline. However first we want to
+ // deal with any trailing comments.
+ token = readUntilSignificantToken();
+
+ // "Early" bail-out if the text does not appear to be minified.
+ // Here we ignore the case where whitespace appears at the end of
+ // the text.
+ if (pushbackToken && token && token.tokenType === "whitespace" &&
+ /\n/g.test(text.substring(token.startOffset, token.endOffset))) {
+ return originalText;
+ }
+
+ // Finally time for that newline.
+ result = result + prettifyCSS.LINE_SEPARATOR;
+
+ // Maybe we hit EOF.
+ if (!pushbackToken) {
+ break;
+ }
+ }
+
+ return result;
+}
+
+exports.prettifyCSS = prettifyCSS;
diff --git a/devtools/shared/inspector/moz.build b/devtools/shared/inspector/moz.build
new file mode 100644
index 000000000..e2c143fc3
--- /dev/null
+++ b/devtools/shared/inspector/moz.build
@@ -0,0 +1,9 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+DevToolsModules(
+ 'css-logic.js'
+)