split up babel core into multiple modules

packages/babel-code-frame/src/index.js

@@ -0,0 +1,115 @@
+import lineNumbers from "line-numbers";
+import repeating from "repeating";
+import jsTokens from "js-tokens";
+import esutils from "esutils";
+import chalk from "chalk";
+
+/**
+ * Chalk styles for token types.
+ */
+
+var defs = {
+  string:     chalk.red,
+  punctuator: chalk.bold,
+  curly:      chalk.green,
+  parens:     chalk.blue.bold,
+  square:     chalk.yellow,
+  keyword:    chalk.cyan,
+  number:     chalk.magenta,
+  regex:      chalk.magenta,
+  comment:    chalk.grey,
+  invalid:    chalk.inverse
+};
+
+/**
+ * RegExp to test for newlines in terminal.
+ */
+
+const NEWLINE = /\r\n|[\n\r\u2028\u2029]/;
+
+/**
+ * Get the type of token, specifying punctuator type.
+ */
+
+function getTokenType(match) {
+  var token = jsTokens.matchToToken(match);
+  if (token.type === "name" && esutils.keyword.isReservedWordES6(token.value)) {
+    return "keyword";
+  }
+
+  if (token.type === "punctuator") {
+    switch (token.value) {
+      case "{":
+      case "}":
+        return "curly";
+      case "(":
+      case ")":
+        return "parens";
+      case "[":
+      case "]":
+        return "square";
+    }
+  }
+
+  return token.type;
+}
+
+/**
+ * Highlight `text`.
+ */
+
+function highlight(text) {
+  return text.replace(jsTokens, function (...args) {
+    var type = getTokenType(args);
+    var colorize = defs[type];
+    if (colorize) {
+      return args[0].split(NEWLINE).map(str => colorize(str)).join("\n");
+    } else {
+      return args[0];
+    }
+  });
+}
+
+/**
+ * Create a code frame, adding line numbers, code highlighting, and pointing to a given position.
+ */
+
+export default function (lines: number, lineNumber: number, colNumber: number, opts = {}): string {
+  colNumber = Math.max(colNumber, 0);
+
+  var highlighted = opts.highlightCode && chalk.supportsColor;
+  if (highlighted) lines = highlight(lines);
+
+  lines = lines.split(NEWLINE);
+
+  var start = Math.max(lineNumber - 3, 0);
+  var end   = Math.min(lines.length, lineNumber + 3);
+
+  if (!lineNumber && !colNumber) {
+    start = 0;
+    end = lines.length;
+  }
+
+  var frame = lineNumbers(lines.slice(start, end), {
+    start: start + 1,
+    before: "  ",
+    after: " | ",
+    transform(params) {
+      if (params.number !== lineNumber) {
+        return;
+      }
+
+      if (colNumber) {
+        params.line += `\n${params.before}${repeating(" ", params.width)}${params.after}${repeating(" ", colNumber - 1)}^`;
+      }
+
+      params.before = params.before.replace(/^./, ">");
+    }
+  }).join("\n");
+
+  if (highlighted) {
+    return chalk.reset(frame);
+  } else {
+    return frame;
+  }
+}