Platform independence pre-check (digital-asset#17955)

* Rename //bazel_tools:match-{cabal=>golden}-file * Generate and check hash file for contents of //compiler/damlc/tests:platform-independence.dar * Add pre-commit hook to test //compiler/damlc/tests:platform-independence-dar-hash-file-matches * Print info when //bazel_tools:match-golden-file fails * platform-independence-dar-check pre-commit hook runs depending on env var * Skip platform-independence-check if RUN_PLATFORM_INDEPENDENCE_CHECK is unset * Document dar_hash_file rules * move platform-independence-checks warning to .envrc * implement generate_dar_hash_file genrule in python in particular, this allows us to produce the same output on all platforms * fix windows * Update rules_daml/daml.bzl * bytes.replace does not operate in place
kgeonw · Dec 7, 2023 · 4794454 · 4794454
1 parent f678ad1
commit 4794454
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Showing 12 changed files with 221 additions and 11 deletions.
diff --git a/.envrc b/.envrc
@@ -19,3 +19,13 @@ for HOOK_TYPE in ${HOOK_TYPES[@]}; do pre-commit uninstall -t "$HOOK_TYPE" > /de
 if [[ -z "${DADE_NO_PRE_COMMIT:-}" ]]; then
     pre-commit install -t "$DADE_PRE_COMMIT_HOOK_TYPE" > /dev/null
 fi
+
+if [ -z "${RUN_PLATFORM_INDEPENDENCE_CHECK:-}" ]; then
+  echo "Warning: platform-independence-checks will be skipped."
+  echo "To silence this warning, please set 'RUN_PLATFORM_INDEPENDENCE_CHECK'"
+  echo "by running the following line:"
+  echo "    echo export RUN_PLATFORM_INDEPENDENCE_CHECK=no  >> $(pwd)/.envrc.private"
+  echo "if you usually work on the compiler, run the following line instead:"
+  echo "    echo export RUN_PLATFORM_INDEPENDENCE_CHECK=yes >> $(pwd)/.envrc.private"
+  export RUN_PLATFORM_INDEPENDENCE_CHECK=no
+fi
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
@@ -46,3 +46,8 @@ repos:
       pass_filenames: false
       entry: "dade-copyright-headers update"
       types: [text]
+    - id: platform-independence-check
+      name: platform-independence-check
+      language: system
+      pass_filenames: false
+      entry: "pre-commit/platform-independence-check.sh"
diff --git a/WORKSPACE b/WORKSPACE
@@ -111,6 +111,16 @@ nixpkgs_cc_configure(
 
 nixpkgs_python_configure(repository = "@nixpkgs") if not is_windows else None
 
+dev_env_tool(
+    name = "python_dev_env",
+    nix_include = ["bogus"],
+    nix_paths = ["bogus"],
+    tools = ["python"],
+    win_include = ["."],
+    win_paths = ["python.exe"],
+    win_tool = "python-3.8.2",
+) if is_windows else None
+
 # Curl system dependency
 nixpkgs_package(
     name = "curl_nix",

diff --git a/bazel_tools/BUILD.bazel b/bazel_tools/BUILD.bazel
@@ -85,7 +85,7 @@ check 'org.scala-lang:scala-reflect (in {maven_install_json})' "$$SCALA_REFLECT_
 ) if not is_windows else None
 
 filegroup(
-    name = "match-cabal-file",
-    srcs = glob(["match-cabal-file.sh"]),
+    name = "match-golden-file",
+    srcs = glob(["match-golden-file.sh"]),
     visibility = ["//visibility:public"],
 )
diff --git a/bazel_tools/haskell.bzl b/bazel_tools/haskell.bzl
@@ -319,10 +319,18 @@ def generate_and_track_cabal(name, exe_name = None, src_dir = None, exclude_deps
         visibility = ["//visibility:public"],
     )
 
+    test_name = name + "-cabal-file-matches"
+
+    lbl = "//{package}:{target}".format(
+        package = native.package_name(),
+        target = test_name,
+    )
+
     native.sh_test(
-        name = name + "-cabal-file-matches",
-        srcs = ["//bazel_tools:match-cabal-file"],
+        name = test_name,
+        srcs = ["//bazel_tools:match-golden-file"],
         args = [
+            lbl,
             "$(location :%s-generated-cabal)" % name,
             "$(location :%s-golden-cabal)" % name,
             "$(POSIX_DIFF)",

diff --git a/bazel_tools/match-cabal-file.sh → bazel_tools/match-golden-file.sh b/bazel_tools/match-cabal-file.sh → bazel_tools/match-golden-file.sh
@@ -11,17 +11,26 @@ source "${RUNFILES_DIR:-/dev/null}/$f" 2>/dev/null || \
   { echo>&2 "ERROR: cannot find $f"; exit 1; }; f=; set -e
 # --- end runfiles.bash initialization v2 ---
 
-GENERATED=$(rlocation "$TEST_WORKSPACE/$1")
-GOLDEN=$(rlocation "$TEST_WORKSPACE/$2")
-DIFF=$3
-ACCEPT=${4:-}
+LABEL=$1
+GENERATED=$(rlocation "$TEST_WORKSPACE/$2")
+GOLDEN=$(rlocation "$TEST_WORKSPACE/$3")
+DIFF=$4
+ACCEPT=${5:-}
+
+info() {
+  echo "diff ($DIFF) failed with exit status: $1"
+  echo "To accept the changes, run"
+  echo "    bazel run $LABEL -- --accept"
+  exit $1
+}
 
 case "$ACCEPT" in
   -a | --accept)
-      echo Accepting changes, copying "$GENERATED" to "$2"
-      cp "$GENERATED" "$2"
+      echo Accepting changes, copying "$GENERATED" to "$3"
+      cp "$GENERATED" "$3"
       ;;
   *)
+      trap 'info $?' ERR
       $DIFF $GENERATED $GOLDEN
       ;;
 esac
diff --git a/compiler/damlc/tests/BUILD.bazel b/compiler/damlc/tests/BUILD.bazel
@@ -4,7 +4,7 @@
 load("//bazel_tools:haskell.bzl", "da_haskell_binary", "da_haskell_library", "da_haskell_test")
 load("@os_info//:os_info.bzl", "is_darwin", "is_windows")
 load(":util.bzl", "damlc_compile_test")
-load("//rules_daml:daml.bzl", "daml_compile", "daml_compile_with_dalf")
+load("//rules_daml:daml.bzl", "daml_compile", "daml_compile_with_dalf", "generate_and_track_dar_hash_file")
 load("@build_environment//:configuration.bzl", "ghc_version", "sdk_version")
 load("//daml-lf/language:daml-lf.bzl", "COMPILER_LF_VERSIONS", "LF_MAJOR_VERSIONS", "lf_version_default_or_latest", "mangle_for_damlc")
 load("//compiler/damlc:util.bzl", "ghc_pkg")
@@ -1190,6 +1190,13 @@ daml_compile_with_dalf(
     ghc_options = [],
 )
 
+# This ensures that changes to the contents of 'platform-independence.dar'
+# don't go unnoticed. This can happen after changes to daml-prim or daml-stdlib.
+# This is likely to happen if you work on the compiler , so it's a good idea to
+# add 'export RUN_PLATFORM_INDEPENDENCE_CHECK=yes' to your '.envrc.private'
+# at the root of the repo.
+generate_and_track_dar_hash_file("platform-independence")
+
 # Desugared daml golden tests
 da_haskell_test(
     name = "daml-desugar",

diff --git a/compiler/damlc/tests/platform-independence.dar-hash b/compiler/damlc/tests/platform-independence.dar-hash
@@ -0,0 +1,34 @@
+f4cbef8a91a8767297778db25b029ac70ebba248c1a5fd10464966e75bf9c245  META-INF/MANIFEST.MF
+b5c40ce08e30cf16a8cad16e2341d01d6ee49984fb8670cd12d7bea4984fae91  platform-independence-1.0.0-aeeeb8902241c9454cba7a1594d2ba19aae4aaa92824bf0dffd513d3f4eb1d71/compiler/damlc/tests/PlatformIndependence.daml
+0000000000000000000000000000000000000000000000000000000000000000  platform-independence-1.0.0-aeeeb8902241c9454cba7a1594d2ba19aae4aaa92824bf0dffd513d3f4eb1d71/compiler/damlc/tests/PlatformIndependence.hi
+0000000000000000000000000000000000000000000000000000000000000000  platform-independence-1.0.0-aeeeb8902241c9454cba7a1594d2ba19aae4aaa92824bf0dffd513d3f4eb1d71/compiler/damlc/tests/PlatformIndependence.hie
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+826cad481a81e8e1fd7151a0f9c3bf5c14cc14e2983e1abc143387dafe4b8282  platform-independence-1.0.0-aeeeb8902241c9454cba7a1594d2ba19aae4aaa92824bf0dffd513d3f4eb1d71/daml-stdlib-DA-Time-Types-733e38d36a2759688a4b2c4cec69d48e7b55ecc8dedc8067b815926c917a182a.dalf
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+1d1014d0027a3582e15a7e23a3e96101cb2c100f1550b776bfc189e583db6c9e  platform-independence-1.0.0-aeeeb8902241c9454cba7a1594d2ba19aae4aaa92824bf0dffd513d3f4eb1d71/data/platform-independence-1.0.0.conf
+7c1281de1ce291c14bb08a84d1d0f990cf3ccfc541380b380352e90a76533be1  platform-independence-1.0.0-aeeeb8902241c9454cba7a1594d2ba19aae4aaa92824bf0dffd513d3f4eb1d71/platform-independence-1.0.0-aeeeb8902241c9454cba7a1594d2ba19aae4aaa92824bf0dffd513d3f4eb1d71.dalf
diff --git a/pre-commit/platform-independence-check.sh b/pre-commit/platform-independence-check.sh
@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+# Copyright (c) 2023 Digital Asset (Switzerland) GmbH and/or its affiliates. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+set -euo pipefail
+
+if [ "$RUN_PLATFORM_INDEPENDENCE_CHECK" = "yes" ]; then
+  bazel test //compiler/damlc/tests:platform-independence-dar-hash-file-matches
+fi
diff --git a/rules_daml/BUILD.bazel b/rules_daml/BUILD.bazel
@@ -6,3 +6,9 @@ exports_files(
     ["daml.bzl"],
     visibility = ["//bazel_tools/docs:__pkg__"],
 )
+
+filegroup(
+    name = "generate-dar-hash",
+    srcs = glob(["generate-dar-hash.py"]),
+    visibility = ["//visibility:public"],
+)
diff --git a/rules_daml/daml.bzl b/rules_daml/daml.bzl
@@ -5,6 +5,7 @@ load("@build_environment//:configuration.bzl", "ghc_version", "sdk_version")
 load("//bazel_tools/sh:sh.bzl", "sh_inline_test")
 load("//daml-lf/language:daml-lf.bzl", "COMPILER_LF_VERSIONS", "version_in")
 load("@bazel_skylib//lib:paths.bzl", "paths")
+load("@os_info//:os_info.bzl", "is_windows")
 
 _damlc = attr.label(
     default = Label("//compiler/damlc:damlc-compile-only"),
@@ -368,6 +369,79 @@ def daml_compile_with_dalf(
         dalf = name + ".dalf",
     )
 
+def generate_and_track_dar_hash_file(name):
+    """
+    Given a 'name', defines the following targets:
+      (1) ':{name}-dar-hash-file-matches',
+      (2) ':{name}-golden-hash'.
+      (3) ':{name}-generated-hash',
+    Target (1) is a test that checks that the files in targets (2) and (3) match.
+    It can also replace (2) with the output of (3) if run with the flag '--accept'.
+    Target (2) is an indirection to the file
+      ':{name}.dar-hash',
+    which must be present in the package where this macro is used.
+    Target (3) is transitively defined by 'generate_dar_hash_file'.
+    """
+    generate_dar_hash_file(name)
+
+    native.filegroup(
+        name = name + "-golden-hash",
+        srcs = native.glob([name + ".dar-hash"]),
+        visibility = ["//visibility:public"],
+    )
+
+    test_name = name + "-dar-hash-file-matches"
+
+    lbl = "//{package}:{target}".format(
+        package = native.package_name(),
+        target = test_name,
+    )
+
+    native.sh_test(
+        name = test_name,
+        srcs = ["//bazel_tools:match-golden-file"],
+        args = [
+            lbl,
+            "$(location :{}-generated-hash)".format(name),
+            "$(location :{}-golden-hash)".format(name),
+            "$(POSIX_DIFF)",
+        ],
+        data = [
+            ":{}-generated-hash".format(name),
+            ":{}-golden-hash".format(name),
+        ],
+        toolchains = [
+            "@rules_sh//sh/posix:make_variables",
+        ],
+        deps = [
+            "@bazel_tools//tools/bash/runfiles",
+        ],
+    )
+
+def generate_dar_hash_file(name):
+    """
+    Given a 'name', defines a target of the form
+      ':{name}-generated-hash'.
+    with a single file of the form
+      ':{name}-generated.dar-hash'.
+    The resulting file will contain one line per file present in
+      ':{name}.dar',
+    sorted by filename and excluding *.hi and *.hie files, where each line
+    has the sha256sum for the file followed by the path of the file relative to
+    the root of the dar.
+    """
+    native.genrule(
+        name = name + "-generated-hash",
+        srcs = ["//rules_daml:generate-dar-hash", ":{}.dar".format(name)],
+        tools = ["@python_dev_env//:python"] if is_windows else [],
+        outs = [name + "-generated.dar-hash"],
+        cmd = "{python} {exe} {dar} > $@".format(
+            python = "$(execpath @python_dev_env//:python)" if is_windows else "python",
+            exe = "$(location //rules_daml:generate-dar-hash)",
+            dar = "$(location :{}.dar)".format(name),
+        ),
+    )
+
 def daml_build_test(
         name,
         project_dir,

diff --git a/rules_daml/generate-dar-hash.py b/rules_daml/generate-dar-hash.py
@@ -0,0 +1,38 @@
+# Copyright (c) 2023 Digital Asset (Switzerland) GmbH and/or its affiliates. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+from argparse import ArgumentParser
+from zipfile import ZipFile
+from pathlib import PurePath
+from hashlib import sha256
+
+
+def parse_args():
+    parser = ArgumentParser(description="generate-dar-hash")
+    parser.add_argument('dar', metavar='DAR', type=str)
+    return parser.parse_args()
+
+
+def entry(filename, bytes):
+    extension = PurePath(filename).suffix
+    if extension in ['.hi', '.hie']:
+        # hie/hi files may differ, so we ignore their contents.
+        hash = 64 * '0'
+    else:
+        if extension in ['.daml']:
+            # on text files, newlines will be encoded differently depending
+            # on platform, so we canonicalize them here
+            bytes = bytes.replace(b'\r\n', b'\n')
+        hash = sha256(bytes).hexdigest()
+    return f"{hash}  {filename}"
+
+
+def main():
+    args = parse_args()
+    with ZipFile(args.dar) as dar:
+        for filename in dar.namelist():
+            print(entry(filename, dar.read(filename)))
+
+
+if __name__ == '__main__':
+    main()