read xcode_version from apple configs

Author: Karim Alweheshy

xcodeproj/internal/custom_toolchain.bzl

@@ -1,41 +1,34 @@
-def _custom_toolchain_impl(ctx):
-    toolchain_name_base = ctx.attr.toolchain_name
 
-    # Create a file to store Xcode version
-    xcode_version_file = ctx.actions.declare_file(toolchain_name_base + "_xcode_version.txt")
+def _get_xcode_product_version(*, xcode_config):
+    raw_version = str(xcode_config.xcode_version())
+    if not raw_version:
+        fail("""\
+`xcode_config.xcode_version` was not set. This is a bazel bug. Try again.
+""")
 
-    # Run xcodebuild to get the Xcode version
-    ctx.actions.run_shell(
-        outputs = [xcode_version_file],
-        command = """
-            # Get Xcode version and clean it for use in filenames
-            xcodebuild -version | head -n 1 | sed 's/Xcode //' | tr -d '.' | tr ' ' '_' > {outfile}
-        """.format(outfile = xcode_version_file.path),
-        mnemonic = "GetXcodeVersion",
-        execution_requirements = {"no-sandbox": "1"},
-    )
+    version_components = raw_version.split(".")
+    if len(version_components) < 4:
+        # This will result in analysis cache misses, but it's better than
+        # failing
+        return raw_version
 
-    # Create a file to store the default toolchain path
-    default_toolchain_path_file = ctx.actions.declare_file(toolchain_name_base + "_default_toolchain_path.txt")
+    return version_components[3]
 
-    # Run xcrun to get the default toolchain path
-    ctx.actions.run_shell(
-        outputs = [default_toolchain_path_file],
-        command = "xcrun --find clang | sed 's|/usr/bin/clang$||' > {outfile}".format(
-            outfile = default_toolchain_path_file.path
-        ),
-        mnemonic = "GetDefaultToolchainPath",
-        execution_requirements = {"no-sandbox": "1"},  # Allow xcrun to access system paths
+
+def _custom_toolchain_impl(ctx):
+    xcode_version = _get_xcode_product_version(
+        xcode_config = ctx.attr._xcode_config[apple_common.XcodeVersionConfig],
     )
 
-    # Declare the output directory for the toolchain
-    toolchain_dir = ctx.actions.declare_directory(toolchain_name_base + ".xctoolchain")
+    toolchain_name_base = ctx.attr.toolchain_name
+    toolchain_dir = ctx.actions.declare_directory(
+        toolchain_name_base + ".{}".format(xcode_version) + ".xctoolchain"
+    )
 
     resolved_overrides = {}
-    override_files = []  # Collect all override files to include in inputs
+    override_files = []
 
     for tool_target, tool_name in ctx.attr.overrides.items():
-        # The key is the target (label), the value is the tool name (string)
         files = tool_target.files.to_list()
         if not files:
             fail("ERROR: Override for '{}' does not produce any files!".format(tool_name))
@@ -45,15 +38,13 @@ def _custom_toolchain_impl(ctx):
                 tool_name, len(files)))
 
         override_file = files[0]
-        override_files.append(override_file)  # Add to list of input files
+        override_files.append(override_file)
         resolved_overrides[tool_name] = override_file.path
 
-    # Generate symlink creation commands dynamically, excluding plist files
     overrides_list = " ".join(["{}={}".format(k, v) for k, v in resolved_overrides.items()])
 
     script_file = ctx.actions.declare_file(toolchain_name_base + "_setup.sh")
 
-    # Use expand_template with simplified substitutions
     ctx.actions.expand_template(
         template = ctx.file._symlink_template,
         output = script_file,
@@ -62,39 +53,49 @@ def _custom_toolchain_impl(ctx):
             "%toolchain_name_base%": toolchain_name_base,
             "%toolchain_dir%": toolchain_dir.path,
             "%overrides_list%": overrides_list,
-            "%default_toolchain_path_file%": default_toolchain_path_file.path,
-            "%xcode_version_file%": xcode_version_file.path,
+            "%xcode_version%": xcode_version,
         },
     )
 
-    # Run the generated shell script
     ctx.actions.run_shell(
-        outputs=[toolchain_dir],
-        inputs=[default_toolchain_path_file, xcode_version_file] + override_files,
-        tools=[script_file],
-        mnemonic = "SymlinkDefaultXcodeToolchain",
-        command=script_file.path,
-        execution_requirements = {"no-sandbox": "1"},
+        outputs = [toolchain_dir],
+        inputs = override_files,
+        tools = [script_file],
+        mnemonic = "CreateCustomToolchain",
+        command = script_file.path,
+        execution_requirements = {
+            "no-sandbox": "1",
+            "no-cache": "1",
+            "local": "1",
+            "requires-darwin": "1",
+        },
+        use_default_shell_env = True,
     )
 
     # Create runfiles with the override files and script file
-    runfiles = ctx.runfiles(files=override_files + [script_file, default_toolchain_path_file, xcode_version_file])
+    runfiles = ctx.runfiles(files = override_files + [script_file])
 
     return [DefaultInfo(
-        files=depset([toolchain_dir]),
-        runfiles=runfiles,
+        files = depset([toolchain_dir]),
+        runfiles = runfiles,
     )]
 
 custom_toolchain = rule(
-    implementation=_custom_toolchain_impl,
-    attrs={
-        "toolchain_name": attr.string(mandatory=True),
+    implementation = _custom_toolchain_impl,
+    attrs = {
+        "toolchain_name": attr.string(mandatory = True),
         "overrides": attr.label_keyed_string_dict(
-            allow_files=True, mandatory=False, default={}
+            allow_files = True, mandatory = False, default = {}
         ),
         "_symlink_template": attr.label(
-            allow_single_file=True,
-            default=Label("//xcodeproj/internal/templates:custom_toolchain_symlink.sh"),
+            allow_single_file = True,
+            default = Label("//xcodeproj/internal/templates:custom_toolchain_symlink.sh"),
+        ),
+        "_xcode_config": attr.label(
+            default = configuration_field(
+                name = "xcode_config_label",
+                fragment = "apple",
+            ),
         ),
     },
 )

xcodeproj/internal/templates/custom_toolchain_symlink.sh

@@ -4,11 +4,13 @@ set -e
 # Define constants within the script
 TOOLCHAIN_NAME_BASE="%toolchain_name_base%"
 TOOLCHAIN_DIR="%toolchain_dir%"
-DEFAULT_TOOLCHAIN_PATH_FILE="%default_toolchain_path_file%"
-XCODE_VERSION_FILE="%xcode_version_file%"
-XCODE_VERSION=$(cat "$XCODE_VERSION_FILE")
-DEFAULT_TOOLCHAIN=$(cat "$DEFAULT_TOOLCHAIN_PATH_FILE")
+XCODE_VERSION="%xcode_version%"
+
+# Get Xcode version and default toolchain path
+DEFAULT_TOOLCHAIN=$(xcrun --find clang | sed 's|/usr/bin/clang$||')
 XCODE_RAW_VERSION=$(xcodebuild -version | head -n 1)
+
+# Define toolchain names
 TOOLCHAIN_NAME="${TOOLCHAIN_NAME_BASE}"
 HOME_TOOLCHAIN_NAME="BazelRulesXcodeProj ${XCODE_VERSION}"
 USER_TOOLCHAIN_PATH="/Users/$(id -un)/Library/Developer/Toolchains/${HOME_TOOLCHAIN_NAME}.xctoolchain"