action.yml

name: "Check formatting of Rust code with rustfmt"
description: |
  Run `cargo fmt` and check Rust code.
  Highlights places which are not correctly formatted.
branding:
  icon: "check-square"
  color: "yellow"

inputs:
  manifest-path:
    description: "Specify the --manifest-path argument to rustfmt"
    required: false
    default: "./Cargo.toml"

runs:
  using: composite
  steps:
    - name: Rustfmt Job Summary
      shell: bash
      run: |
        # Run cargo and store the original output
        CARGO_STATUS=0
        CARGO_OUTPUT=$(cargo fmt --all --manifest-path=${{ inputs.manifest-path }} -- --color=always --check 2>/dev/null) || CARGO_STATUS=$?

        if [ ${CARGO_STATUS} -eq 0 ]; then
            cat <<MARKDOWN_INTRO >> $GITHUB_STEP_SUMMARY
        # Rustfmt Results

        The code is formatted perfectly!
        MARKDOWN_INTRO
        else
            cat <<MARKDOWN_INTRO >> $GITHUB_STEP_SUMMARY
        # Rustfmt Results

        \`cargo fmt\` reported formatting errors in the following locations.
        You can fix them by executing the following command and committing the changes.
        \`\`\`bash
        cargo fmt --all
        \`\`\`
        MARKDOWN_INTRO

            echo "${CARGO_OUTPUT}" |
                # Strip color codes
                sed 's/\x1B\[[0-9;]*[A-Za-z]\x0f\?//g' |
                # Strip (some) cursor movements
                sed 's/\x1B.[A-G]//g' |
                tr "\n" "\r" |
                # Wrap each location into a HTML details
                sed -E 's#Diff in ([^\r]*?)( at line |:)([[:digit:]]+):\r((:?[ +-][^\r]*\r)+)#<details>\n<summary>\1:\3</summary>\n\n```diff\n\4```\n\n</details>\n\n#g' |
                tr "\r" "\n" >> $GITHUB_STEP_SUMMARY
        fi

        # Print the original cargo message
        echo "${CARGO_OUTPUT}"
        # Exit with the same status as cargo
        exit "${CARGO_STATUS}"