Shell Test Mocking Pattern FAQs

Question 1

Can I use this for unit testing internal shell functions?

Accepted Answer

This pattern is specifically designed for integration testing of scripts that call external binaries. For testing internal shell functions in isolation, function-level mocking or standard unit testing frameworks are typically more appropriate.

Question 2

How do I verify that a command was actually called?

Accepted Answer

Each mock script is designed to append its name and all passed arguments to a shared 'mock.log' file. After the script under test finishes, you can use grep or similar tools to assert that specific strings exist in that log.

Question 3

Does this pattern work if my script uses absolute paths?

Accepted Answer

No. If a script calls a command using an absolute path (e.g., /usr/bin/grep), it will bypass the PATH environment variable and execute the real binary. This pattern only works for commands called by their name.

Question 4

Is this compatible with Zsh or just Bash?

Accepted Answer

The shell-test-mock-path-pattern is shell-agnostic and works with any POSIX-compliant shell, including Bash, Zsh, and Dash, making it highly portable across different development environments.

Question 5

How does this pattern intercept external commands?

Accepted Answer

The pattern creates a temporary directory containing executable 'mock' scripts named after the real commands. By prepending this directory to the PATH environment variable during test execution, the shell finds and runs the mocks instead of the system binaries.

Shell Test Mocking Pattern

Shell Test Mocking Pattern

主な機能

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主な機能

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