decaffeinate lib/ui/highlighter

lib/ui/highlighter.js

@@ -0,0 +1,81 @@
+'use babel'
+import _ from 'underscore-plus';
+
+// Implementation identical to https://github.com/atom/highlights/blob/master/src/highlights.coffee,
+// but uses an externally provided grammar.
+  // Highlights some `text` according to the specified `grammar`.
+export function highlight(text, grammar, {scopePrefix, block}={}) {
+    if (scopePrefix == null) { scopePrefix = ''; }
+    if (block == null) { block = false; }
+    const lineTokens = grammar.tokenizeLines(text);
+
+    // Remove trailing newline
+    if (lineTokens.length > 0) {
+      const lastLineTokens = lineTokens[lineTokens.length - 1];
+
+      if ((lastLineTokens.length === 1) && (lastLineTokens[0].value === '')) {
+        lineTokens.pop();
+      }
+    }
+
+    let html = '<code class="editor editor-colors">';
+    for (let tokens of lineTokens) {
+      const scopeStack = [];
+      html += `<${block ? "div" : "span"} class=\"line\">`;
+      for (let {value, scopes} of tokens) {
+        if (!value) { value = ' '; }
+        html = this.updateScopeStack(scopeStack, scopes, html, scopePrefix);
+        html += `<span>${this.escapeString(value)}</span>`;
+      }
+      while (scopeStack.length > 0) { html = this.popScope(scopeStack, html); }
+      html += `</${block ? "div" : "span"}>`;
+    }
+    html += '</code>';
+    return html;
+}
+
+export function escapeString(string) {
+    string.replace(/[&"'<> ]/g, function(match) {
+      switch (match) {
+        case '&': return '&amp;';
+        case '"': return '&quot;';
+        case "'": return '&#39;';
+        case '<': return '&lt;';
+        case '>': return '&gt;';
+        case ' ': return '&nbsp;';
+        default: return match;
+      }
+    });
+}
+
+export function updateScopeStack(scopeStack, desiredScopes, html, scopePrefix) {
+    let excessScopes = scopeStack.length - desiredScopes.length;
+    if (excessScopes > 0) {
+      while (excessScopes--) { html = this.popScope(scopeStack, html); }
+    }
+
+    // pop until common prefix
+    let i;
+    for (i = scopeStack.length; i<=0; i--) {
+      if (_.isEqual(scopeStack.slice(0, i), desiredScopes.slice(0, i))) { break; }
+      html = this.popScope(scopeStack, html);
+    }
+
+    // push on top of common prefix until scopeStack is desiredScopes
+    for (let j = i; i <= desiredScopes.length; j++ ) {
+      html = this.pushScope(scopeStack, desiredScopes[j], html, scopePrefix);
+    }
+
+    return html;
+}
+
+export function pushScope(scopeStack, scope, html, scopePrefix) {
+    scopeStack.push(scope);
+    const className = scopePrefix + scope.replace(/\.+/g, ` ${scopePrefix}`);
+    html += `<span class=\"${className}\">`;
+}
+
+export function popScope(scopeStack, html) {
+    scopeStack.pop();
+    html += '</span>';
+}