improve toolchain

Author: Karim Alweheshy

test/internal/custom_toolchain/BUILD

@@ -11,11 +11,10 @@ filegroup(
 # Test target for custom_toolchain
 custom_toolchain(
     name = "test_toolchain",
+    toolchain_name = "TestCustomToolchain",
     overrides = {
-        # Key is a label target, value is the tool name
         ":test_swiftc": "swiftc",
     },
-    toolchain_name = "TestCustomToolchain",
 )
 
 # Add a simple test rule that depends on the toolchain

test/internal/custom_toolchain/custom_toolchain_test.sh

@@ -20,8 +20,8 @@ if [[ ! -f "$TOOLCHAIN_DIR/ToolchainInfo.plist" ]]; then
 fi
 
 # Check for correct identifiers in the plist
-if ! grep -q "BazelRulesXcodeProj" "$TOOLCHAIN_DIR/ToolchainInfo.plist"; then
-  echo "ERROR: ToolchainInfo.plist doesn't contain BazelRulesXcodeProj"
+if ! grep -q "TestCustomToolchain" "$TOOLCHAIN_DIR/ToolchainInfo.plist"; then
+  echo "ERROR: ToolchainInfo.plist doesn't contain TestCustomToolchain"
   exit 1
 fi
 

xcodeproj/internal/custom_toolchain.bzl

@@ -1,5 +1,7 @@
 """Implementation of the `custom_toolchain` rule."""
 
+load("//xcodeproj/internal:providers.bzl", "ToolchainInfo")
+
 def _get_xcode_product_version(*, xcode_config):
     raw_version = str(xcode_config.xcode_version())
     if not raw_version:
@@ -21,31 +23,38 @@ def _custom_toolchain_impl(ctx):
     )
 
     toolchain_name_base = ctx.attr.toolchain_name
-    toolchain_dir = ctx.actions.declare_directory(
-        toolchain_name_base + "{}".format(xcode_version) + ".xctoolchain",
-    )
+    toolchain_id = "com.rules_xcodeproj.{}.{}".format(toolchain_name_base, xcode_version)
+    full_toolchain_name = "{}{}".format(toolchain_name_base, xcode_version)
+    toolchain_dir = ctx.actions.declare_directory(full_toolchain_name + ".xctoolchain")
 
     resolved_overrides = {}
     override_files = []
 
-    for tool_target, tool_name in ctx.attr.overrides.items():
-        files = tool_target.files.to_list()
+    # Process tools from comma-separated list
+    for stub_target, tools_str in ctx.attr.overrides.items():
+        files = stub_target.files.to_list()
         if not files:
-            fail("ERROR: Override for '{}' does not produce any files!".format(tool_name))
+            fail("ERROR: Override stub does not produce any files!")
 
         if len(files) > 1:
-            fail("ERROR: Override for '{}' produces multiple files ({}). Each override must have exactly one file.".format(
-                tool_name,
-                len(files),
-            ))
+            fail("ERROR: Override stub produces multiple files ({}). Each stub must have exactly one file.".format(
+                len(files)))
+
+        stub_file = files[0]
+        if stub_file not in override_files:
+            override_files.append(stub_file)
 
-        override_file = files[0]
-        override_files.append(override_file)
-        resolved_overrides[tool_name] = override_file.path
+        # Split comma-separated list of tool names
+        tool_names = [name.strip() for name in tools_str.split(",")]
+
+        # Add an entry for each tool name
+        for tool_name in tool_names:
+            if tool_name:  # Skip empty names
+                resolved_overrides[tool_name] = stub_file.path
 
     overrides_list = " ".join(["{}={}".format(k, v) for k, v in resolved_overrides.items()])
 
-    script_file = ctx.actions.declare_file(toolchain_name_base + "_setup.sh")
+    script_file = ctx.actions.declare_file(full_toolchain_name + "_setup.sh")
 
     ctx.actions.expand_template(
         template = ctx.file._symlink_template,
@@ -54,8 +63,9 @@ def _custom_toolchain_impl(ctx):
         substitutions = {
             "%overrides_list%": overrides_list,
             "%toolchain_dir%": toolchain_dir.path,
-            "%toolchain_name_base%": toolchain_name_base,
+            "%toolchain_name_base%": full_toolchain_name,
             "%xcode_version%": xcode_version,
+            "%toolchain_id%": toolchain_id,
         },
     )
 
@@ -74,23 +84,30 @@ def _custom_toolchain_impl(ctx):
         use_default_shell_env = True,
     )
 
-    # Create runfiles with the override files and script file
     runfiles = ctx.runfiles(files = override_files + [script_file])
 
-    return [DefaultInfo(
-        files = depset([toolchain_dir]),
-        runfiles = runfiles,
-    )]
+    toolchain_provider = ToolchainInfo(
+        name = full_toolchain_name,
+        identifier = toolchain_id,
+    )
+
+    return [
+        DefaultInfo(
+            files = depset([toolchain_dir]),
+            runfiles = runfiles,
+        ),
+        toolchain_provider,
+    ]
 
 custom_toolchain = rule(
     implementation = _custom_toolchain_impl,
     attrs = {
+        "toolchain_name": attr.string(mandatory = True),
         "overrides": attr.label_keyed_string_dict(
             allow_files = True,
-            mandatory = False,
-            default = {},
+            mandatory = True,
+            doc = "Map from stub target to comma-separated list of tool names that should use that stub",
         ),
-        "toolchain_name": attr.string(mandatory = True),
         "_symlink_template": attr.label(
             allow_single_file = True,
             default = Label("//xcodeproj/internal/templates:custom_toolchain_symlink.sh"),
@@ -102,4 +119,4 @@ custom_toolchain = rule(
             ),
         ),
     },
-)
+)

xcodeproj/internal/providers.bzl

@@ -15,3 +15,11 @@ XcodeProjRunnerOutputInfo = provider(
         "runner": "The xcodeproj runner.",
     },
 )
+
+ToolchainInfo = provider(
+    doc = "Information about the custom toolchain",
+    fields = {
+        "name": "The full name of the toolchain",
+        "identifier": "The bundle identifier of the toolchain",
+    },
+)

xcodeproj/internal/templates/custom_toolchain_symlink.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-set -e
+set -euo pipefail
 
 # Define constants within the script
 TOOLCHAIN_NAME_BASE="%toolchain_name_base%"
@@ -17,6 +17,10 @@ BUILT_TOOLCHAIN_PATH="$PWD/$TOOLCHAIN_DIR"
 
 mkdir -p "$TOOLCHAIN_DIR"
 
+# Parse overrides into a file for safer processing
+OVERRIDES_FILE=$(mktemp)
+echo "%overrides_list%" > "$OVERRIDES_FILE"
+
 # Process all files from the default toolchain
 find "$DEFAULT_TOOLCHAIN" -type f -o -type l | while read -r file; do
     base_name="$(basename "$file")"
@@ -30,27 +34,40 @@ find "$DEFAULT_TOOLCHAIN" -type f -o -type l | while read -r file; do
     # Ensure parent directory exists
     mkdir -p "$TOOLCHAIN_DIR/$(dirname "$rel_path")"
 
-    # Process overrides
+    # Check if this file has an override
     override_found=false
-    while IFS='=' read -r key value; do
-        if [[ "$key" == "$base_name" ]]; then
-            value="$PWD/$value"
-            cp "$value" "$TOOLCHAIN_DIR/$rel_path"
-            # Make executable if original is executable
-            if [[ -x "$file" ]]; then
-                chmod +x "$TOOLCHAIN_DIR/$rel_path"
-            fi
+    override_value=""
+
+    for override in $(cat "$OVERRIDES_FILE"); do
+        KEY="${override%%=*}"
+        VALUE="${override#*=}"
+
+        if [[ "$KEY" == "$base_name" ]]; then
+            override_value="$VALUE"
             override_found=true
             break
         fi
-    done <<< "%overrides_list%"
+    done
 
-    # If no override found, symlink the original
-    if [[ "$override_found" == "false" ]]; then
+    # Apply the override or create symlink
+    if [[ "$override_found" == "true" ]]; then
+        # Make path absolute
+        override_path="$PWD/$override_value"
+        cp "$override_path" "$TOOLCHAIN_DIR/$rel_path"
+
+        # Make executable if original is executable
+        if [[ -x "$file" ]]; then
+            chmod +x "$TOOLCHAIN_DIR/$rel_path"
+        fi
+    else
+        # If no override found, symlink the original
         ln -sf "$file" "$TOOLCHAIN_DIR/$rel_path"
     fi
 done
 
+# Clean up
+rm -f "$OVERRIDES_FILE"
+
 # Generate the ToolchainInfo.plist directly with Xcode version information
 cat > "$TOOLCHAIN_DIR/ToolchainInfo.plist" << EOF
 <?xml version="1.0" encoding="UTF-8"?>