How to use the command parallel-lint (with examples)

Parallel-lint is a tool used to check the syntax of PHP files in parallel. It can be particularly useful when working with large PHP projects or when trying to speed up the linting process. This article will illustrate various use cases of the parallel-lint command.

Use case 1: Lint a specific directory

Code:

parallel-lint path/to/directory

Motivation:

The motivation for using this example is to lint a specific directory and check if there are any syntax errors in the PHP files within that directory. By specifying the path to the directory, the command will recursively check all PHP files in that directory and its subdirectories.

Explanation:

• parallel-lint: The name of the command.
• path/to/directory: The path to the directory that you want to lint.

Example output:

Checking path/to/directory/file1.php - OK
Checking path/to/directory/file2.php - Error: Syntax error on line 10
...
Summary: Total files checked: 2, Total errors found: 1

Use case 2: Lint a directory using the specified number of parallel processes

Code:

parallel-lint -j processes path/to/directory

Motivation:

The motivation for using this example is to control the number of parallel processes being used while linting a directory. By specifying the number of processes, you can optimize the linting process based on the available resources and the size of the directory.

Explanation:

• parallel-lint: The name of the command.
• -j processes: The -j option followed by the number of parallel processes to be used.
• path/to/directory: The path to the directory that you want to lint.

Example output:

Checking path/to/directory/file1.php - OK
Checking path/to/directory/file2.php - Error: Syntax error on line 10
...
Summary: Total files checked: 2, Total errors found: 1

Use case 3: Lint a directory, excluding the specified directory

Code:

parallel-lint --exclude path/to/excluded_directory path/to/directory

Motivation:

The motivation for using this example is to lint a directory while excluding a specific directory from the linting process. This can be useful when there are directories within the main directory that you do not want to include in the linting process.

Explanation:

• parallel-lint: The name of the command.
• --exclude path/to/excluded_directory: The --exclude option followed by the path to the directory that you want to exclude.
• path/to/directory: The path to the directory that you want to lint.

Example output:

Checking path/to/directory/file1.php - OK
Checking path/to/directory/file2.php - Error: Syntax error on line 10
...
Summary: Total files checked: 2, Total errors found: 1

Use case 4: Lint a directory of files using a comma-separated list of extension(s)

Code:

parallel-lint -e php,html,phpt path/to/directory

Motivation:

The motivation for using this example is to lint a directory of files based on specific extensions. By specifying the extensions, you can limit the linting process to the specified file types only.

Explanation:

• parallel-lint: The name of the command.
• -e php,html,phpt: The -e option followed by a comma-separated list of extensions to be linted.
• path/to/directory: The path to the directory that you want to lint.

Example output:

Checking path/to/directory/file1.php - OK
Checking path/to/directory/file2.html - OK
Checking path/to/directory/file3.phpt - Error: Syntax error on line 10
...
Summary: Total files checked: 3, Total errors found: 1

Use case 5: Lint a directory and output the results as JSON

Code:

parallel-lint --json path/to/directory

Motivation:

The motivation for using this example is to obtain the linting results in a JSON format. This can be useful when integrating the linting process with other tools or when further processing of the linting results is required.

Explanation:

• parallel-lint: The name of the command.
• --json: The --json option to output the results as JSON.
• path/to/directory: The path to the directory that you want to lint.

Example output:

{
  "path/to/directory/file1.php": {
    "status": "OK",
    "errors": []
  },
  "path/to/directory/file2.php": {
    "status": "Error",
    "errors": [
      {
        "line": 10,
        "message": "Syntax error"
      }
    ]
  },
  "summary": {
    "total_files": 2,
    "total_errors": 1
  }
}

Use case 6: Lint a directory and show Git Blame results for rows containing errors

Code:

parallel-lint --blame path/to/directory

Motivation:

The motivation for using this example is to show Git Blame results for the rows containing errors in the linting process. This can be useful for identifying the author and commit information associated with the lines of code that have syntax errors.

Explanation:

• parallel-lint: The name of the command.
• --blame: The --blame option to show Git Blame results.
• path/to/directory: The path to the directory that you want to lint.

Example output:

Checking path/to/directory/file1.php - OK
Checking path/to/directory/file2.php - Error: Syntax error on line 10 (Author: John Doe, Commit: abcdefg)
...
Summary: Total files checked: 2, Total errors found: 1

Conclusion:

Parallel-lint is a powerful tool for checking the syntax of PHP files in parallel. By understanding the various use cases provided in this article, you can effectively utilize the parallel-lint command to optimize your linting process and improve code quality.