Annotate AssertionErrors thrown due to improper usage

Author: novemberborn

lib/assert.js

@@ -17,6 +17,7 @@ class AssertionError extends Error {
 
 		this.assertion = opts.assertion;
 		this.fixedSource = opts.fixedSource;
+		this.improperUsage = opts.improperUsage || false;
 		this.operator = opts.operator;
 		this.values = opts.values || [];
 
@@ -130,6 +131,7 @@ function wrapAssertions(callbacks) {
 			} else if (typeof fn !== 'function') {
 				fail(this, new AssertionError({
 					assertion: 'throws',
+					improperUsage: true,
 					message: '`t.throws()` must be called with a function, Promise, or Observable',
 					values: [formatAssertError.formatWithLabel('Called with:', fn)]
 				}));
@@ -200,6 +202,7 @@ function wrapAssertions(callbacks) {
 			} else if (typeof fn !== 'function') {
 				fail(this, new AssertionError({
 					assertion: 'notThrows',
+					improperUsage: true,
 					message: '`t.notThrows()` must be called with a function, Promise, or Observable',
 					values: [formatAssertError.formatWithLabel('Called with:', fn)]
 				}));
@@ -315,13 +318,15 @@ function wrapAssertions(callbacks) {
 			if (typeof string !== 'string') {
 				throw new AssertionError({
 					assertion: 'regex',
+					improperUsage: true,
 					message: '`t.regex()` must be called with a string',
 					values: [formatAssertError.formatWithLabel('Called with:', string)]
 				});
 			}
 			if (!(regex instanceof RegExp)) {
 				throw new AssertionError({
 					assertion: 'regex',
+					improperUsage: true,
 					message: '`t.regex()` must be called with a regular expression',
 					values: [formatAssertError.formatWithLabel('Called with:', regex)]
 				});
@@ -343,13 +348,15 @@ function wrapAssertions(callbacks) {
 			if (typeof string !== 'string') {
 				throw new AssertionError({
 					assertion: 'notRegex',
+					improperUsage: true,
 					message: '`t.notRegex()` must be called with a string',
 					values: [formatAssertError.formatWithLabel('Called with:', string)]
 				});
 			}
 			if (!(regex instanceof RegExp)) {
 				throw new AssertionError({
 					assertion: 'notRegex',
+					improperUsage: true,
 					message: '`t.notRegex()` must be called with a regular expression',
 					values: [formatAssertError.formatWithLabel('Called with:', regex)]
 				});

lib/serialize-error.js

@@ -61,6 +61,7 @@ module.exports = error => {
 	}
 
 	if (retval.avaAssertionError) {
+		retval.improperUsage = error.improperUsage;
 		retval.message = error.message;
 		retval.name = error.name;
 		retval.statements = error.statements;