Fixes to macos setup and CARGO_PROFILE_DEV_DEBUG (#22)

* ensure that homebrew is available on mac

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

* Repair Homebrew permissions and preserve dev debug information

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

* Remove unnecessary Homebrew ownership restriction

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

---------

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: simongdavies

README.md

@@ -36,6 +36,10 @@ Rustup reads the version, profile, components, and targets from each toolchain
 file. Put required extras such as `clippy`, `rustfmt`, `x86_64-unknown-none`,
 or cross-compilation targets in those files.
 
+The action defaults `CARGO_PROFILE_DEV_DEBUG` to `2` before Rust setup so
+development builds retain full debug information. Explicit caller values,
+including `0` or `false`, are preserved.
+
 ## Overview
 
 This action performs the following steps:
@@ -50,8 +54,11 @@ This action performs the following steps:
 
 Runners need Bash 5 and rustup or curl. On macOS, the action discovers Homebrew
 on PATH or in its standard Apple Silicon and Intel locations, installing it
-noninteractively with the official installer when missing. Installing Homebrew
-requires the runner user to have the permissions required by that installer.
+noninteractively with the official installer when missing. If an existing
+installation is not writable, the action reruns the official installer to repair
+its permissions and checks them again before continuing. Installation and repair
+require the runner user to have the permissions required by that installer,
+including noninteractive sudo access when ownership changes are needed.
 The Rust setup action installs rustup when missing and Bash through Homebrew
 on macOS.
 

action.yml

@@ -19,7 +19,11 @@ runs:
       if: ${{ runner.os == 'macOS' }}
       run: |
         find_brew() {
-          command -v brew && return 0
+          local candidate
+          if candidate="$(command -v brew)" && [ -x "$candidate" ]; then
+            echo "$candidate"
+            return 0
+          fi
           for candidate in /opt/homebrew/bin/brew /usr/local/bin/brew; do
             if [ -x "$candidate" ]; then
               echo "$candidate"
@@ -29,7 +33,29 @@ runs:
           return 1
         }
 
-        if ! brew="$(find_brew)"; then
+        brew_is_writable() {
+          prefix="$("$brew" --prefix)" || return 1
+          repository="$("$brew" --repository)" || return 1
+          for directory in "$prefix" "$repository" \
+              "$prefix/Cellar" "$prefix/Frameworks" "$prefix/bin" \
+              "$prefix/etc" "$prefix/etc/bash_completion.d" \
+              "$prefix/include" "$prefix/lib" "$prefix/lib/pkgconfig" \
+              "$prefix/opt" "$prefix/sbin" "$prefix/share" \
+              "$prefix/share/doc" "$prefix/share/man" \
+              "$prefix/share/man/man1" "$prefix/share/man/man3" \
+              "$prefix/share/man/man5" "$prefix/share/man/man7" \
+              "$prefix/share/zsh" "$prefix/share/zsh/site-functions" \
+              "$prefix/var/homebrew" "$prefix/var/homebrew/linked" \
+              "$prefix/var/homebrew/locks"; do
+            if [ -e "$directory" ] && [ ! -w "$directory" ]; then
+              echo "Homebrew directory is not writable: $directory" >&2
+              return 1
+            fi
+          done
+        }
+
+        if ! brew="$(find_brew)" || ! brew_is_writable; then
+          echo "Installing or repairing Homebrew for $(id -un)."
           installer="$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
           NONINTERACTIVE=1 /bin/bash -c "$installer"
           if ! brew="$(find_brew)"; then
@@ -38,10 +64,22 @@ runs:
           fi
         fi
 
+        if ! brew_is_writable; then
+          echo "::error::Homebrew is still not writable after running its installer. Check runner sudo permissions and Homebrew ownership."
+          exit 1
+        fi
+
         prefix="$("$brew" --prefix)"
         printf '%s\n' "$prefix/bin" "$prefix/sbin" >> "$GITHUB_PATH"
       shell: bash
 
+    - name: Preserve development debug information
+      run: |
+        if [ -z "${CARGO_PROFILE_DEV_DEBUG+x}" ]; then
+          echo "CARGO_PROFILE_DEV_DEBUG=2" >> "$GITHUB_ENV"
+        fi
+      shell: bash
+
     - name: Install Rust toolchain
       uses: actions-rust-lang/setup-rust-toolchain@ecabd13d1c56bd1345c230e542e9144811ad706f # v2
       with: