Add src/common/utils/colors.ts (#782)

This is a thin wrapper around the 'ansi-colors' module, which will be used if it can be found.

This interface may also support HTML colorization in the future.

Will be used to make the mental parsing of expectation failures easier.

package.json

@@ -40,6 +40,7 @@
     "@types/offscreencanvas": "^2019.6.2",
     "@typescript-eslint/parser": "^4.22.0",
     "@webgpu/types": "^0.1.6",
+    "ansi-colors": "4.1.1",
     "babel-plugin-add-header-comment": "^1.0.3",
     "babel-plugin-const-enum": "^1.0.1",
     "chokidar": "^3.4.3",

src/common/util/colors.ts

@@ -0,0 +1,123 @@
+/**
+ * The interface used for formatting strings to contain color metadata.
+ *
+ * Use the interface properties to construct a style, then use the
+ * `(s: string): string` function to format the provided string with the given
+ * style.
+ */
+export interface Colors {
+  // Returns the string formatted to contain the specified color or style.
+  (s: string): string;
+
+  // modifiers
+  reset: Colors;
+  bold: Colors;
+  dim: Colors;
+  italic: Colors;
+  underline: Colors;
+  inverse: Colors;
+  hidden: Colors;
+  strikethrough: Colors;
+
+  // colors
+  black: Colors;
+  red: Colors;
+  green: Colors;
+  yellow: Colors;
+  blue: Colors;
+  magenta: Colors;
+  cyan: Colors;
+  white: Colors;
+  gray: Colors;
+  grey: Colors;
+
+  // bright colors
+  blackBright: Colors;
+  redBright: Colors;
+  greenBright: Colors;
+  yellowBright: Colors;
+  blueBright: Colors;
+  magentaBright: Colors;
+  cyanBright: Colors;
+  whiteBright: Colors;
+
+  // background colors
+  bgBlack: Colors;
+  bgRed: Colors;
+  bgGreen: Colors;
+  bgYellow: Colors;
+  bgBlue: Colors;
+  bgMagenta: Colors;
+  bgCyan: Colors;
+  bgWhite: Colors;
+
+  // bright background colors
+  bgBlackBright: Colors;
+  bgRedBright: Colors;
+  bgGreenBright: Colors;
+  bgYellowBright: Colors;
+  bgBlueBright: Colors;
+  bgMagentaBright: Colors;
+  bgCyanBright: Colors;
+  bgWhiteBright: Colors;
+}
+
+/**
+ * The interface used for formatting strings with color metadata.
+ *
+ * Currently Colors will use the 'ansi-colors' module if it can be loaded.
+ * If it cannot be loaded, then the Colors implementation is a straight pass-through.
+ *
+ * Colors may also be a no-op if the current environment does not support colors.
+ */
+export let Colors: Colors;
+
+try {
+  /* eslint-disable-next-line node/no-unpublished-require */
+  Colors = require('ansi-colors') as Colors;
+} catch {
+  const passthrough = ((s: string) => s) as Colors;
+  passthrough.reset = passthrough;
+  passthrough.bold = passthrough;
+  passthrough.dim = passthrough;
+  passthrough.italic = passthrough;
+  passthrough.underline = passthrough;
+  passthrough.inverse = passthrough;
+  passthrough.hidden = passthrough;
+  passthrough.strikethrough = passthrough;
+  passthrough.black = passthrough;
+  passthrough.red = passthrough;
+  passthrough.green = passthrough;
+  passthrough.yellow = passthrough;
+  passthrough.blue = passthrough;
+  passthrough.magenta = passthrough;
+  passthrough.cyan = passthrough;
+  passthrough.white = passthrough;
+  passthrough.gray = passthrough;
+  passthrough.grey = passthrough;
+  passthrough.blackBright = passthrough;
+  passthrough.redBright = passthrough;
+  passthrough.greenBright = passthrough;
+  passthrough.yellowBright = passthrough;
+  passthrough.blueBright = passthrough;
+  passthrough.magentaBright = passthrough;
+  passthrough.cyanBright = passthrough;
+  passthrough.whiteBright = passthrough;
+  passthrough.bgBlack = passthrough;
+  passthrough.bgRed = passthrough;
+  passthrough.bgGreen = passthrough;
+  passthrough.bgYellow = passthrough;
+  passthrough.bgBlue = passthrough;
+  passthrough.bgMagenta = passthrough;
+  passthrough.bgCyan = passthrough;
+  passthrough.bgWhite = passthrough;
+  passthrough.bgBlackBright = passthrough;
+  passthrough.bgRedBright = passthrough;
+  passthrough.bgGreenBright = passthrough;
+  passthrough.bgYellowBright = passthrough;
+  passthrough.bgBlueBright = passthrough;
+  passthrough.bgMagentaBright = passthrough;
+  passthrough.bgCyanBright = passthrough;
+  passthrough.bgWhiteBright = passthrough;
+  Colors = passthrough;
+}