ExpressionAssertion

Defined in: packages/engine/src/testing/index.ts:225

Assertions about the result of one evaluated expression, returned by expectExpression. Every matcher returns this, so assertions chain, and throws an ExpectationError when it fails.

Constructors

Constructor

new ExpressionAssertion(expression, outcome): ExpressionAssertion;

Defined in: packages/engine/src/testing/index.ts:226

Parameters

Parameter	Type
expression	string
outcome	Outcome

Returns

ExpressionAssertion

Accessors

value

Get Signature

get value(): Value;

Defined in: packages/engine/src/testing/index.ts:232

The raw resolved Value, for an assertion the matchers do not cover. Throws if the expression failed.

Returns

Value

Methods

toBeError()

toBeError(): this;

Defined in: packages/engine/src/testing/index.ts:312

Assert the expression failed (a thrown engine error or a plugin-raised error value). Says nothing about the code.

Returns

this

---

toBePending()

toBePending(): this;

Defined in: packages/engine/src/testing/index.ts:355

Assert the expression returned a value still resolving asynchronously. The kit evaluates synchronously, so a package whose result comes from an async resolver reports pending on first evaluation, this is how a test confirms the async path was taken without resolving it.

Returns

this

---

toEqual()

toEqual(expected, unit?): this;

Defined in: packages/engine/src/testing/index.ts:268

Assert the expression evaluated to expected, and, when unit is given, that the result carries exactly that unit. A number compares against the value’s numeric magnitude within a small floating-point tolerance; a string compares against the value’s own string; a boolean against its boolean reading. Omitting unit leaves the unit unchecked, so toEqual(5) passes for both 5 and 5 gp.

Parameters

Parameter	Type
expected	string | number | boolean
unit?	string

Returns

this

---

toEvaluate()

toEvaluate(): this;

Defined in: packages/engine/src/testing/index.ts:248

Assert the expression evaluated to a value (not an error, not a pending async result). Says nothing about what the value is.

Returns

this

---

toFailWith()

toFailWith(code): this;

Defined in: packages/engine/src/testing/index.ts:329

Assert the expression failed with exactly code, the error catalog code (e.g. "UNDEFINED_VARIABLE", or a package’s own code). Reports the code it actually got when they differ, so a near-miss is obvious.

Parameters

Parameter	Type
code	string

Returns

this