diff options
Diffstat (limited to 'third_party/bazel/rules_haskell/haskell/repl.bzl')
| -rw-r--r-- | third_party/bazel/rules_haskell/haskell/repl.bzl | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/third_party/bazel/rules_haskell/haskell/repl.bzl b/third_party/bazel/rules_haskell/haskell/repl.bzl new file mode 100644 index 000000000000..7480c03add6e --- /dev/null +++ b/third_party/bazel/rules_haskell/haskell/repl.bzl @@ -0,0 +1,460 @@ +"""Multi target Haskell REPL.""" + +load("@bazel_skylib//lib:paths.bzl", "paths") +load("@bazel_skylib//lib:shell.bzl", "shell") +load("@io_tweag_rules_haskell//haskell:private/context.bzl", "haskell_context", "render_env") +load( + "@io_tweag_rules_haskell//haskell:private/path_utils.bzl", + "link_libraries", + "match_label", + "parse_pattern", + "target_unique_name", +) +load( + "@io_tweag_rules_haskell//haskell:providers.bzl", + "HaskellInfo", + "HaskellLibraryInfo", + "empty_HaskellCcInfo", + "get_libs_for_ghc_linker", + "merge_HaskellCcInfo", +) +load("@io_tweag_rules_haskell//haskell:private/set.bzl", "set") + +HaskellReplLoadInfo = provider( + doc = """Haskell REPL target information. + + Information to a Haskell target to load into the REPL as source. + """, + fields = { + "source_files": "Set of files that contain Haskell modules.", + "cc_dependencies": "Direct cc library dependencies. See HaskellCcInfo.", + "compiler_flags": "Flags to pass to the Haskell compiler.", + "repl_ghci_args": "Arbitrary extra arguments to pass to GHCi. This extends `compiler_flags` and `repl_ghci_args` from the toolchain", + }, +) + +HaskellReplDepInfo = provider( + doc = """Haskell REPL dependency information. + + Information to a Haskell target to load into the REPL as a built package. + """, + fields = { + "package_ids": "Set of workspace unique package identifiers.", + "package_databases": "Set of package cache files.", + }, +) + +HaskellReplCollectInfo = provider( + doc = """Collect Haskell REPL information. + + Holds information to generate a REPL that loads some targets as source + and some targets as built packages. + """, + fields = { + "load_infos": "Dictionary from labels to HaskellReplLoadInfo.", + "dep_infos": "Dictionary from labels to HaskellReplDepInfo.", + "prebuilt_dependencies": "Transitive collection of info of wired-in Haskell dependencies.", + "transitive_cc_dependencies": "Transitive cc library dependencies. See HaskellCcInfo.", + }, +) + +HaskellReplInfo = provider( + doc = """Haskell REPL information. + + Holds information to generate a REPL that loads a specific set of targets + from source or as built packages. + """, + fields = { + "load_info": "Combined HaskellReplLoadInfo.", + "dep_info": "Combined HaskellReplDepInfo.", + "prebuilt_dependencies": "Transitive collection of info of wired-in Haskell dependencies.", + "transitive_cc_dependencies": "Transitive cc library dependencies. See HaskellCcInfo.", + }, +) + +def _merge_HaskellReplLoadInfo(load_infos): + source_files = set.empty() + cc_dependencies = empty_HaskellCcInfo() + compiler_flags = [] + repl_ghci_args = [] + + for load_info in load_infos: + set.mutable_union(source_files, load_info.source_files) + cc_dependencies = merge_HaskellCcInfo( + cc_dependencies, + load_info.cc_dependencies, + ) + compiler_flags += load_info.compiler_flags + repl_ghci_args += load_info.repl_ghci_args + + return HaskellReplLoadInfo( + source_files = source_files, + cc_dependencies = cc_dependencies, + compiler_flags = compiler_flags, + repl_ghci_args = repl_ghci_args, + ) + +def _merge_HaskellReplDepInfo(dep_infos): + package_ids = set.empty() + package_databases = set.empty() + + for dep_info in dep_infos: + set.mutable_union(package_ids, dep_info.package_ids) + set.mutable_union(package_databases, dep_info.package_databases) + + return HaskellReplDepInfo( + package_ids = package_ids, + package_databases = package_databases, + ) + +def _create_HaskellReplCollectInfo(target, ctx): + load_infos = {} + dep_infos = {} + + hs_info = target[HaskellInfo] + prebuilt_dependencies = hs_info.prebuilt_dependencies + transitive_cc_dependencies = hs_info.transitive_cc_dependencies + + load_infos[target.label] = HaskellReplLoadInfo( + source_files = hs_info.source_files, + cc_dependencies = hs_info.cc_dependencies, + compiler_flags = getattr(ctx.rule.attr, "compiler_flags", []), + repl_ghci_args = getattr(ctx.rule.attr, "repl_ghci_args", []), + ) + if HaskellLibraryInfo in target: + lib_info = target[HaskellLibraryInfo] + dep_infos[target.label] = HaskellReplDepInfo( + package_ids = set.singleton(lib_info.package_id), + package_databases = hs_info.package_databases, + ) + + return HaskellReplCollectInfo( + load_infos = load_infos, + dep_infos = dep_infos, + prebuilt_dependencies = prebuilt_dependencies, + transitive_cc_dependencies = transitive_cc_dependencies, + ) + +def _merge_HaskellReplCollectInfo(args): + load_infos = {} + dep_infos = {} + prebuilt_dependencies = set.empty() + transitive_cc_dependencies = empty_HaskellCcInfo() + for arg in args: + load_infos.update(arg.load_infos) + dep_infos.update(arg.dep_infos) + set.mutable_union( + prebuilt_dependencies, + arg.prebuilt_dependencies, + ) + transitive_cc_dependencies = merge_HaskellCcInfo( + transitive_cc_dependencies, + arg.transitive_cc_dependencies, + ) + + return HaskellReplCollectInfo( + load_infos = load_infos, + dep_infos = dep_infos, + prebuilt_dependencies = prebuilt_dependencies, + transitive_cc_dependencies = transitive_cc_dependencies, + ) + +def _load_as_source(from_source, from_binary, lbl): + """Whether a package should be loaded by source or as binary.""" + for pat in from_binary: + if match_label(pat, lbl): + return False + + for pat in from_source: + if match_label(pat, lbl): + return True + + return False + +def _create_HaskellReplInfo(from_source, from_binary, collect_info): + """Convert a HaskellReplCollectInfo to a HaskellReplInfo. + + Args: + from_source: List of patterns for packages to load by source. + from_binary: List of patterns for packages to load as binary packages. + collect_info: HaskellReplCollectInfo provider. + + Returns: + HaskellReplInfo provider. + """ + + # Collect all packages to load by source. + load_info = _merge_HaskellReplLoadInfo([ + load_info + for (lbl, load_info) in collect_info.load_infos.items() + if _load_as_source(from_source, from_binary, lbl) + ]) + + # Collect all packages to load as binary packages. + dep_info = _merge_HaskellReplDepInfo([ + dep_info + for (lbl, dep_info) in collect_info.dep_infos.items() + if not _load_as_source(from_source, from_binary, lbl) + ]) + + return HaskellReplInfo( + load_info = load_info, + dep_info = dep_info, + prebuilt_dependencies = collect_info.prebuilt_dependencies, + transitive_cc_dependencies = collect_info.transitive_cc_dependencies, + ) + +def _create_repl(hs, ctx, repl_info, output): + """Build a multi target REPL. + + Args: + hs: Haskell context. + ctx: Rule context. + repl_info: HaskellReplInfo provider. + output: The output for the executable REPL script. + + Returns: + List of providers: + DefaultInfo provider for the executable REPL script. + + """ + + # The base and directory packages are necessary for the GHCi script we use + # (loads source files and brings in scope the corresponding modules). + args = ["-package", "base", "-package", "directory"] + + # Load prebuilt dependencies (-package) + for dep in set.to_list(repl_info.prebuilt_dependencies): + args.extend(["-package", dep.package]) + + # Load built dependencies (-package-id, -package-db) + for package_id in set.to_list(repl_info.dep_info.package_ids): + args.extend(["-package-id", package_id]) + for package_cache in set.to_list(repl_info.dep_info.package_databases): + args.extend([ + "-package-db", + paths.join("$RULES_HASKELL_EXEC_ROOT", package_cache.dirname), + ]) + + # Load C library dependencies + link_ctx = repl_info.load_info.cc_dependencies.dynamic_linking + libs_to_link = link_ctx.dynamic_libraries_for_runtime.to_list() + + # External C libraries that we need to make available to the REPL. + libraries = link_libraries(libs_to_link, args) + + # Transitive library dependencies to have in runfiles. + (library_deps, ld_library_deps, ghc_env) = get_libs_for_ghc_linker( + hs, + repl_info.transitive_cc_dependencies, + path_prefix = "$RULES_HASKELL_EXEC_ROOT", + ) + library_path = [paths.dirname(lib.path) for lib in library_deps] + ld_library_path = [paths.dirname(lib.path) for lib in ld_library_deps] + + # Load source files + # Force loading by source with `:add *...`. + # See https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/ghci.html#ghci-cmd-:add + add_sources = [ + "*" + f.path + for f in set.to_list(repl_info.load_info.source_files) + ] + ghci_repl_script = hs.actions.declare_file( + target_unique_name(hs, "ghci-repl-script"), + ) + hs.actions.expand_template( + template = ctx.file._ghci_repl_script, + output = ghci_repl_script, + substitutions = { + "{ADD_SOURCES}": " ".join(add_sources), + "{COMMANDS}": "\n".join(ctx.attr.repl_ghci_commands), + }, + ) + args += [ + "-ghci-script", + paths.join("$RULES_HASKELL_EXEC_ROOT", ghci_repl_script.path), + ] + + # Extra arguments. + # `compiler flags` is the default set of arguments for the repl, + # augmented by `repl_ghci_args`. + # The ordering is important, first compiler flags (from toolchain + # and local rule), then from `repl_ghci_args`. This way the more + # specific arguments are listed last, and then have more priority in + # GHC. + # Note that most flags for GHCI do have their negative value, so a + # negative flag in `repl_ghci_args` can disable a positive flag set + # in `compiler_flags`, such as `-XNoOverloadedStrings` will disable + # `-XOverloadedStrings`. + quote_args = ( + hs.toolchain.compiler_flags + + repl_info.load_info.compiler_flags + + hs.toolchain.repl_ghci_args + + repl_info.load_info.repl_ghci_args + + ctx.attr.repl_ghci_args + ) + + hs.actions.expand_template( + template = ctx.file._ghci_repl_wrapper, + output = output, + is_executable = True, + substitutions = { + "{ENV}": render_env(ghc_env), + "{TOOL}": hs.tools.ghci.path, + "{ARGS}": " ".join( + args + [ + shell.quote(a) + for a in quote_args + ], + ), + }, + ) + + extra_inputs = [ + hs.tools.ghci, + ghci_repl_script, + ] + extra_inputs.extend(set.to_list(repl_info.load_info.source_files)) + extra_inputs.extend(set.to_list(repl_info.dep_info.package_databases)) + extra_inputs.extend(library_deps) + extra_inputs.extend(ld_library_deps) + return [DefaultInfo( + executable = output, + runfiles = ctx.runfiles( + files = extra_inputs, + collect_data = ctx.attr.collect_data, + ), + )] + +def _haskell_repl_aspect_impl(target, ctx): + if not HaskellInfo in target: + return [] + + target_info = _create_HaskellReplCollectInfo(target, ctx) + deps_infos = [ + dep[HaskellReplCollectInfo] + for dep in ctx.rule.attr.deps + if HaskellReplCollectInfo in dep + ] + collect_info = _merge_HaskellReplCollectInfo([target_info] + deps_infos) + + # This aspect currently does not generate an executable REPL script by + # itself. This could be extended in future. Note, to that end it's + # necessary to construct a Haskell context without `ctx.attr.name`. + + return [collect_info] + +haskell_repl_aspect = aspect( + implementation = _haskell_repl_aspect_impl, + attr_aspects = ["deps"], +) +""" +Haskell REPL aspect. + +Used to implement the haskell_repl rule. Does not generate an executable REPL +by itself. +""" + +def _haskell_repl_impl(ctx): + collect_info = _merge_HaskellReplCollectInfo([ + dep[HaskellReplCollectInfo] + for dep in ctx.attr.deps + if HaskellReplCollectInfo in dep + ]) + from_source = [parse_pattern(ctx, pat) for pat in ctx.attr.experimental_from_source] + from_binary = [parse_pattern(ctx, pat) for pat in ctx.attr.experimental_from_binary] + repl_info = _create_HaskellReplInfo(from_source, from_binary, collect_info) + hs = haskell_context(ctx) + return _create_repl(hs, ctx, repl_info, ctx.outputs.repl) + +haskell_repl = rule( + implementation = _haskell_repl_impl, + attrs = { + "_ghci_repl_script": attr.label( + allow_single_file = True, + default = Label("@io_tweag_rules_haskell//haskell:assets/ghci_script"), + ), + "_ghci_repl_wrapper": attr.label( + allow_single_file = True, + default = Label("@io_tweag_rules_haskell//haskell:private/ghci_repl_wrapper.sh"), + ), + "deps": attr.label_list( + aspects = [haskell_repl_aspect], + doc = "List of Haskell targets to load into the REPL", + ), + "experimental_from_source": attr.string_list( + doc = """White-list of targets to load by source. + + Wild-card targets such as //... or //:all are allowed. + + The black-list takes precedence over the white-list. + + Note, this attribute will change depending on the outcome of + https://github.com/bazelbuild/bazel/issues/7763. + """, + default = ["//..."], + ), + "experimental_from_binary": attr.string_list( + doc = """Black-list of targets to not load by source but as packages. + + Wild-card targets such as //... or //:all are allowed. + + The black-list takes precedence over the white-list. + + Note, this attribute will change depending on the outcome of + https://github.com/bazelbuild/bazel/issues/7763. + """, + default = [], + ), + "repl_ghci_args": attr.string_list( + doc = "Arbitrary extra arguments to pass to GHCi. This extends `compiler_flags` and `repl_ghci_args` from the toolchain", + default = [], + ), + "repl_ghci_commands": attr.string_list( + doc = "Arbitrary extra commands to execute in GHCi.", + default = [], + ), + "collect_data": attr.bool( + doc = "Whether to collect the data runfiles from the dependencies in srcs, data and deps attributes.", + default = True, + ), + }, + executable = True, + outputs = { + "repl": "%{name}@repl", + }, + toolchains = ["@io_tweag_rules_haskell//haskell:toolchain"], +) +"""Build a REPL for multiple targets. + +Example: + ```bzl + haskell_repl( + name = "repl", + deps = [ + "//lib:some_lib", + "//exe:some_exe", + ], + experimental_from_source = [ + "//lib/...", + "//exe/...", + "//common/...", + ], + experimental_from_binary = [ + "//lib/vendored/...", + ], + ) + ``` + + Collects all transitive Haskell dependencies from `deps`. Those that match + `experimental_from_binary` or are defined in an external workspace will be + loaded as binary packages. Those that match `experimental_from_source` and + are defined in the local workspace will be loaded by source. + + You can call the REPL like this: + +``` +$ bazel run //:repl +``` + +""" |