cargo-test-json-2-html

Convert cargo test JSON output to beautiful, self-contained HTML reports.

Features

• 🎨 Beautiful HTML reports - Clean, modern design with responsive layout
• 📊 Test statistics - Pass/fail/ignored counts
• 🔍 Detailed test output - Collapsible stdout/stderr for each test
• 🛡️ Robust error handling - Gracefully handles mixed JSON/non-JSON output
• 📱 Self-contained - Single HTML file with inline CSS and JavaScript
• 🔗 Source linking - Configurable source code links

📋 Example Report

Installation

Most users will probably want to integrate this as a library into an existing test runner system. However, absent of that, it is possible to run it as a CLI as well:

cargo install --locked cargo-test-json-2-html

Usage

Basic Usage

Generate JSON test output and convert to HTML:

# Generate test report
cargo +nightly test -- --format json -Z unstable-options --show-output > test-output.json 2>&1
cargo-test-json-2-html -i test-output.json -o report.html

Pipeline Usage

# Direct pipeline (requires nightly Rust)
cargo +nightly test -- --format json -Z unstable-options --show-output 2>&1 | cargo-test-json-2-html -o report.html

Library Usage

use cargo_test_json_2_html::{convert_to_html, Config, SourceLinker};

// Basic usage
let json_output = r#"{ "type": "test", "name": "my_test", "event": "ok" }"#;
let config = Config::default();
let html = convert_to_html(json_output, config);

// With custom source linking
struct GitHubLinker {
    repo: String,
}

impl SourceLinker for GitHubLinker {
    fn link(&self, file: &str, line: u32) -> Option<String> {
        Some(format!("https://github.com/{}/blob/main/{}#L{}", self.repo, file, line))
    }
}

let config = Config::builder()
    .source_linker(Box::new(GitHubLinker {
        repo: "user/repo".to_string()
    }))
    .build();
let html = convert_to_html(json_output, config);

CLI Options

cargo-test-json-2-html [OPTIONS]

Options:
  -i, --input <INPUT>    Input file (use - for stdin) [default: -]
  -o, --output <OUTPUT>  Output file (use - for stdout) [default: -]
  -h, --help             Print help

Examples

Generate Report for Current Project

# Run tests and generate HTML report
cargo +nightly test -- --format json -Z unstable-options --show-output > test-results.json 2>&1
cargo-test-json-2-html -i test-results.json -o test-report.html
open test-report.html  # macOS
# or
xdg-open test-report.html  # Linux

CI/CD Integration

# GitHub Actions example
- name: Run tests and generate report
  run: |
    cargo +nightly test -- --format json -Z unstable-options --show-output > test-results.json 2>&1 || true
    cargo-test-json-2-html -i test-results.json -o test-report.html

- name: Upload test report
  uses: actions/upload-artifact@v3
  with:
    name: test-report
    path: test-report.html

Error Handling

The tool gracefully handles various input scenarios:

• Mixed output: Compilation messages mixed with JSON test results
• Invalid JSON: Malformed JSON lines are reported as errors
• Empty input: Generates a valid report even with no tests
• Parsing errors: Full error context included in the HTML report

Requirements

• For JSON output: Rust nightly (for --format json -Z unstable-options)
• For the tool: Rust stable (1.70+)

Output Format

The generated HTML report includes:

• Summary statistics with pass/fail/ignored counts
• Failed tests section with full error output
• Passed tests section with stdout/stderr (collapsible)
• Ignored tests section
• Parsing errors section (if any)
• Raw output section for non-JSON lines

Contributing

Contributions welcome! Please check the issues for planned features.

Development and Debugging

To generate a test report for debugging the HTML output:

# Generate test output from this project
cargo +nightly test -- --format json -Z unstable-options --show-output > test-output.json 2>&1

# Convert to HTML report
cargo run -- -i test-output.json -o test-report.html

# Open the report
open test-report.html  # macOS
# or
xdg-open test-report.html  # Linux

This will create a report showing the actual test results from this project, including any failures, which is useful for testing the HTML generation and styling.

License

MIT OR Apache-2.0