/approval-tests

Java Inline Approvals

Inline approvals store expected output directly in test code using Java text blocks (""").

Contents

• Basic Usage
• InlineOptions Modes
• With Code Display
• Kotlin Support
• How It Works
• When to Use Inline vs File Approvals

Basic Usage

import org.approvaltests.Approvals;
import org.approvaltests.core.Options;

@Test
void testGreeting() {
    var expected = """
        Hello World!
        Welcome to inline approvals!
        """;
    Approvals.verify(getGreeting(), new Options().inline(expected));
}

When the test fails, the framework automatically updates expected with the actual output.

InlineOptions Modes

Automatic Mode

Auto-approves and updates source code immediately:

var expected = "";
Approvals.verify(actual, new Options().inline(expected, InlineOptions.automatic()));

Semi-Automatic Mode

Adds a marker that must be manually deleted to approve:

var expected = """
    actual output here
    ***** DELETE ME TO APPROVE *****
    """;
Approvals.verify(actual, new Options().inline(expected, InlineOptions.semiAutomatic()));

Delete the ***** DELETE ME TO APPROVE ***** line to approve.

Semi-Automatic with Previous

Shows previous approved value for comparison:

var expected = """
    new output
    vvvvv PREVIOUS RESULT vvvvv
    old output
    """;
Approvals.verify(actual, new Options().inline(expected,
    InlineOptions.semiAutomaticWithPreviousApproved()));

With Code Display

Show source code context in diff:

Approvals.verify(actual, new Options().inline(expected, InlineOptions.showCode(true)));

Kotlin Support

Uses Kotlin string templates with trimIndent():

@Test
fun `test greeting`() {
    val expected = """
        Hello World!
        Welcome to inline approvals!
        """.trimIndent()
    Approvals.verify(getGreeting(), Options().inline(expected))
}

How It Works

1. Test fails → InlineJavaReporter activates
2. Reporter finds test method via stack trace
3. Parses source file and locates the expected variable
4. Replaces the text block content with actual output
5. Rewrites source file

When to Use Inline vs File Approvals

Use inline when:

• Output is short (few lines)
• You want test and expectation in one place
• Quick iteration during TDD

Use file approvals when:

• Output is long or complex
• Multiple tests share similar output patterns
• Binary content (images, PDFs)
• JSON/XML that benefits from syntax highlighting