String Assertions

Table of Contents

1. toMatch
2. toNotMatch
3. toInclude
4. toExclude
5. toHaveLength

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toMatch

expect(item: string).toMatch(pattern: RegExp, message?: string): this;

Asserts that the string item matches the regular expression pattern.

Outputs an optional message in case of a failed assertion.

Example

expect('I am a string').toMatch(/^.*string$/);

expect('I am a string').toMatch(/^.*number$/); // Assertion Error

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toNotMatch

expect(item: string).toNotMatch(pattern: RegExp, message?: string): this;

Asserts that the string item does not match the regular expression pattern.

Outputs an optional message in case of a failed assertion.

expect('I am a string').toNotMatch(/^.*number$/);

expect('I am a string').toNotMatch(/^.*string$/); // Assertion Error

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toInclude

expect(item: string).toInclude(value: string, message?: string): this;

Asserts that the string item contains the string value.

Outputs an optional message in case of a failed assertion.

Example

expect('I am a string').toInclude('am');

expect('I am a string').toInclude('not'); // Assertion Error

Aliases

• toContain

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toExclude

expect(item: string).toExclude(value: string, message?: string): this;

Asserts that the string item does not include the string value.

Outputs an optional message in case of a failed assertion.

Example

expect('I am a string').toExclude('not');

expect('I am a string').toExclude('am'); // Assertion Error

Aliases

• toNotInclude
• toNotContain

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toHaveLength

expect(item: string).toHaveLength(value: number, message?: string): this;

Asserts that the length of the string item is equal to value.

Example

expect('I am a string!').toHaveLength(14);

expect('I am a string!').toHaveLength(10); // Assertion Error