LibJS/Tests: Improve expectation error details

1 files changed, 12 insertions, 7 deletions

diff --git a/Userland/Libraries/LibJS/Tests/test-common.js b/Userland/Libraries/LibJS/Tests/test-common.js
index eaf107d0ed..ec54dfddf2 100644
--- a/Userland/Libraries/LibJS/Tests/test-common.js
+++ b/Userland/Libraries/LibJS/Tests/test-common.js
@@ -65,8 +65,7 @@ class ExpectationError extends Error {
             this.__doMatcher(() => {
                 this.__expect(
                     Object.is(this.target, value),
-                    () =>
-                        "toBe: expected _" + String(value) + "_, got _" + String(this.target) + "_"
+                    () => `toBe: expected _${String(value)}_, got _${String(this.target)}_`
                 );
             });
         }
@@ -75,11 +74,11 @@ class ExpectationError extends Error {
         toBeCloseTo(value) {
             this.__expect(
                 typeof this.target === "number",
-                () => "toBeCloseTo: target not of type number"
+                () => `toBeCloseTo: expected target of type number, got ${typeof value}`
             );
             this.__expect(
                 typeof value === "number",
-                () => "toBeCloseTo: argument not of type number"
+                () => `toBeCloseTo: expected argument of type number, got ${typeof value}`
             );
 
             this.__doMatcher(() => {
@@ -133,7 +132,10 @@ class ExpectationError extends Error {
 
         toBeDefined() {
             this.__doMatcher(() => {
-                this.__expect(this.target !== undefined, () => "toBeDefined: target was undefined");
+                this.__expect(
+                    this.target !== undefined,
+                    () => "toBeDefined: expected target to be defined, got undefined"
+                );
             });
         }
 
@@ -153,7 +155,10 @@ class ExpectationError extends Error {
             this.__doMatcher(() => {
                 this.__expect(
                     this.target === undefined,
-                    () => "toBeUndefined: target was not undefined"
+                    () =>
+                        `toBeUndefined: expected target to be undefined, got _${String(
+                            this.target
+                        )}_`
                 );
             });
         }
@@ -162,7 +167,7 @@ class ExpectationError extends Error {
             this.__doMatcher(() => {
                 this.__expect(
                     isNaN(this.target),
-                    () => "toBeNaN: target was _" + String(this.target) + "_, not NaN"
+                    () => `toBeNaN: expected target to be NaN, got _${String(this.target)}_`
                 );
             });
         }