Coverage

Requirement

Install lcov with follow this installation

info

LCOV is an extension of GCOV, a GNU tool which provides information about what parts of a program are actually executed (i.e. "covered") while running a particular test case. The extension consists of a set of Perl scripts which build on the textual GCOV output to implement the following enhanced functionality:

* HTML based output: coverage rates are additionally indicated using bar
  graphs and specific colors.

* Support for large projects: overview pages allow quick browsing of
  coverage data by providing either a hierarchical directory structure
  view or a three-level detail view: directory, file and source code view.

LCOV was initially designed to support Linux kernel coverage measurements, but works as well for coverage measurements on standard user space applications.

check your installation with run:

morpheme coverage

Prerequisites

You must have lcov installed to generate HTML reports.

• macOS: brew install lcov
• Ubuntu: apt-get install lcov
• Windows: (Not fully supported automatically) Install Perl and LCOV manually.

Verify installation:

lcov --version

Configuration (morpheme.yaml)

You can configure output directories and exclude specific files from the coverage report (e.g., generated code, mocks) in your morpheme.yaml.

coverage:
  output_html_dir: "coverage/html" # Directory for the HTML report
  remove:
    - "**/generated/**"
    - "**/mock/**"
    - "**/*.g.dart"
    - "**/*.freezed.dart"

Description

The coverage command performs the following steps:

1. Execute Tests: Runs flutter test --coverage across your project.
2. Merge Results: Combines lcov.info files from the main project, core, and all features.
3. Filter: Removes files matching the patterns defined in morpheme.yaml.
4. Generate Report: Creates an HTML site in coverage/html (or your configured path) to visualize line-by-line coverage.

Usage

Coverage for Entire Project

morpheme coverage

Coverage for Specific Scopes

You can limit the coverage analysis to a specific app, feature, or page to save time.

# Analyze specific app
morpheme coverage -a driver

# Analyze specific feature
morpheme coverage -f auth

# Analyze specific page
morpheme coverage -f auth -p login

Custom Reporters

Output test results to different formats or files, useful for CI/CD integration.

morpheme coverage --reporter json --file-reporter json:report.json

Options

morpheme coverage [options]

To see all available options and flags, run morpheme coverage --help.

Available Options

Option	Abbr	Description
--apps	-a	Generate coverage for a specific app.
--feature	-f	Generate coverage for a specific feature.
--page	-p	Generate coverage for a specific page.
--reporter	-r	output format: compact (default), expanded, json, github, etc.
--file-reporter		Save results to file. Format: <reporter>:<filepath>.
--morpheme-yaml		Path to a custom configuration file.