feat: support report error cause (#308)

Co-authored-by: Pooya Parsa <[email protected]>

examples/error.ts

@@ -0,0 +1,13 @@
+import { consola } from "./utils";
+
+const error = new Error("This is an error", {
+  cause: new Error("This is the cause", {
+    cause: new Error("This is the cause of the cause"),
+  }),
+});
+
+console.error(error);
+
+console.log("\n");
+
+consola.error(error);

src/reporters/basic.ts

@@ -12,13 +12,27 @@ const bracket = (x: string) => (x ? `[${x}]` : "");
 
 export class BasicReporter implements ConsolaReporter {
   formatStack(stack: string, opts: FormatOptions) {
-    return "  " + parseStack(stack).join("\n  ");
+    const indent = "  ".repeat((opts?.errorLevel || 0) + 1);
+    return indent + parseStack(stack).join(`\n${indent}`);
+  }
+
+  formatError(err: any, opts: FormatOptions): string {
+    const message = err.message ?? formatWithOptions(opts, err);
+    const stack = err.stack ? this.formatStack(err.stack, opts) : "";
+
+    const level = opts?.errorLevel || 0;
+    const causedPrefix = level > 0 ? `${"  ".repeat(level)}[cause]: ` : "";
+    const causedError = err.cause
+      ? "\n\n" + this.formatError(err.cause, { ...opts, errorLevel: level + 1 })
+      : "";
+
+    return causedPrefix + message + "\n" + stack + causedError;
   }
 
   formatArgs(args: any[], opts: FormatOptions) {
     const _args = args.map((arg) => {
       if (arg && typeof arg.stack === "string") {
-        return arg.message + "\n" + this.formatStack(arg.stack, opts);
+        return this.formatError(arg, opts);
       }
       return arg;
     });

src/reporters/fancy.ts

@@ -46,9 +46,10 @@ function stringWidth(str: string) {
 }
 
 export class FancyReporter extends BasicReporter {
-  formatStack(stack: string) {
+  formatStack(stack: string, opts: FormatOptions) {
+    const indent = "  ".repeat((opts?.errorLevel || 0) + 1);
     return (
-      "\n" +
+      `\n${indent}` +
       parseStack(stack)
         .map(
           (line) =>
@@ -57,7 +58,7 @@ export class FancyReporter extends BasicReporter {
               .replace(/^at +/, (m) => colors.gray(m))
               .replace(/\((.+)\)/, (_, m) => `(${colors.cyan(m)})`),
         )
-        .join("\n")
+        .join(`\n${indent}`)
     );
   }
 

src/types.ts

@@ -90,6 +90,11 @@ export interface FormatOptions {
    */
   compact?: boolean | number;
 
+  /**
+   * Error cause level.
+   */
+  errorLevel?: number;
+
   /**
    * Allows additional custom formatting options.
    */