Merge 9b0bf26e8d into 27b5d3b55f

The tool is used to find the latest commit, from the HEAD in date order,
that is compatible with the specified Zig compiler.

The commit found can be used as a base for a branch that can be used by
users that can only install a released version of Zig, e.g. v0.10.1.

tools/find-zig-release-branch.sh

@@ -0,0 +1,72 @@
+#!/bin/sh
+# Find the latest commit that is compatible with a specified Zig version, like
+# 0.10.1.
+#
+# The zig executable can be set using the ZIG_EXE environment variable.
+#
+# This script will clone the ziglings repository to the path specified by the
+# first parameter, that is required.  Commits are processed in date order.
+
+# Heals all the exercises.
+heal() {
+    if [ ! -d exercises ]
+    then
+        echo "Must be run from the project root directory."
+        exit 1
+    fi
+
+    mkdir -p patches/healed
+    for original in exercises/*.zig; do
+        name=$(basename "$original" .zig)
+        patch_name="patches/patches/$name.patch"
+        output="patches/healed/$name.zig"
+
+        if [ -f "$patch_name" ]; then
+            patch -i "$patch_name" -o "$output" -s "$original"
+        else
+            printf "Cannot heal %s: no patch found\n" "$name"
+        fi
+    done
+}
+
+# Configure input parameters.
+if [ -z "$ZIG_EXE" ]; then
+    echo '$ZIG_EXE is required'
+    exit 1
+fi
+
+work_path="$1"
+if [ -z "$work_path" ] ; then
+    echo "The work_path parameter is required and must be a directory"
+    exit 1
+elif [ ! -d "$work_path" ]; then
+    printf "%s does not exist\n" "$work_path"
+    exit 1
+fi
+
+# Clone ziglings repository.
+cd "$work_path" || exit 1
+echo "Cloning into 'ziglings'"
+git clone -q https://github.com/ratfactor/ziglings.git ziglings || exit 1
+
+# Find a commit compatible with the specified Zig version.
+cd ziglings || exit 1
+for commit in $(git log --date-order --pretty=format:"%H"); do
+    git checkout --detach -q "$commit"
+    printf "\nTesting commit %s\n" "$commit"
+
+    heal
+
+    # Some versions exits with exit code 0 instead of 1, if version check fails.
+    sed -i 's/exit(0)/exit(1)/g' build.zig
+
+    "$ZIG_EXE" build -Dhealed
+    zig_ret=$?
+
+    git restore build.zig
+
+    if [ "$zig_ret" -eq 0 ]; then
+        printf "Find working commit: %s\n" "$commit"
+        exit 0
+    fi
+done