feat(typescript): support for declarationdir on ts_project (#2048)

* feat(typescript): support for declarationdir on ts_project

* refactor: rename ts_library attributes to the snake_case version of their TypeScript names

--outDir == out_dir
--declarationDir == declaration_dir
--rootDir == root_dir

Note this is non-breaking since none of these attributes are on the 1.x branch

packages/typescript/internal/ts_project.bzl

@@ -11,10 +11,11 @@ _DEFAULT_TSC = (
 
 _ATTRS = {
     "args": attr.string_list(),
+    "declaration_dir": attr.string(),
     "deps": attr.label_list(providers = [DeclarationInfo]),
     "extends": attr.label_list(allow_files = [".json"]),
-    "outdir": attr.string(),
-    "rootdir": attr.string(),
+    "out_dir": attr.string(),
+    "root_dir": attr.string(),
     # NB: no restriction on extensions here, because tsc sometimes adds type-check support
     # for more file kinds (like require('some.json')) and also
     # if you swap out the `compiler` attribute (like with ngtsc)
@@ -56,14 +57,15 @@ def _ts_project_impl(ctx):
         "--project",
         ctx.file.tsconfig.path,
         "--outDir",
-        _join(ctx.bin_dir.path, ctx.label.package, ctx.attr.outdir),
+        _join(ctx.bin_dir.path, ctx.label.package, ctx.attr.out_dir),
         "--rootDir",
-        _join(ctx.label.package, ctx.attr.rootdir) if ctx.label.package else ".",
+        _join(ctx.label.package, ctx.attr.root_dir) if ctx.label.package else ".",
     ])
     if len(ctx.outputs.typings_outs) > 0:
+        declaration_dir = ctx.attr.declaration_dir if ctx.attr.declaration_dir else ctx.attr.out_dir
         arguments.add_all([
             "--declarationDir",
-            _join(ctx.bin_dir.path, ctx.label.package, ctx.attr.outdir),
+            _join(ctx.bin_dir.path, ctx.label.package, declaration_dir),
         ])
 
     # When users report problems, we can ask them to re-build with
@@ -98,13 +100,13 @@ def _ts_project_impl(ctx):
         inputs.extend(ctx.files.extends)
 
     # We do not try to predeclare json_outs, because their output locations generally conflict with their path in the source tree.
-    # (The exception is when outdir is used, then the .json output is a different path than the input.)
+    # (The exception is when out_dir is used, then the .json output is a different path than the input.)
     # However tsc will copy .json srcs to the output tree so we want to declare these outputs to include along with .js Default outs
     # NB: We don't have emit_declaration_only setting here, so use presence of any JS outputs as an equivalent.
     # tsc will only produce .json if it also produces .js
     if len(ctx.outputs.js_outs):
         json_outs = [
-            ctx.actions.declare_file(_join(ctx.attr.outdir, src.short_path[len(ctx.label.package) + 1:]))
+            ctx.actions.declare_file(_join(ctx.attr.out_dir, src.short_path[len(ctx.label.package) + 1:]))
             for src in ctx.files.srcs
             if src.basename.endswith(".json")
         ]
@@ -115,7 +117,7 @@ def _ts_project_impl(ctx):
     if ctx.outputs.buildinfo_out:
         outputs.append(ctx.outputs.buildinfo_out)
     runtime_outputs = depset(json_outs + ctx.outputs.js_outs + ctx.outputs.map_outs)
-    typings_outputs = ctx.outputs.typings_outs + [s for s in ctx.files.srcs if s.path.endswith(".d.ts")]
+    typings_outputs = ctx.outputs.typings_outs + ctx.outputs.typing_maps_outs + [s for s in ctx.files.srcs if s.path.endswith(".d.ts")]
 
     if len(outputs) > 0:
         run_node(
@@ -230,8 +232,9 @@ def ts_project_macro(
         emit_declaration_only = False,
         tsc = None,
         validate = True,
-        outdir = None,
-        rootdir = None,
+        declaration_dir = None,
+        out_dir = None,
+        root_dir = None,
         **kwargs):
     """Compiles one TypeScript project using `tsc --project`
 
@@ -357,13 +360,21 @@ def ts_project_macro(
 
         validate: boolean; whether to check that the tsconfig settings match the attributes.
 
-        outdir: a string specifying a subdirectory under the bazel-out folder where outputs are written.
+        root_dir: a string specifying a subdirectory under the input package which should be consider the
+            root directory of all the input files.
+            Equivalent to the TypeScript --rootDir option.
+            By default it is '.', meaning the source directory where the BUILD file lives.
+
+        out_dir: a string specifying a subdirectory under the bazel-out folder where outputs are written.
+            Equivalent to the TypeScript --outDir option.
             Note that Bazel always requires outputs be written under a subdirectory matching the input package,
-            so if your rule appears in path/to/my/package/BUILD.bazel and outdir = "foo" then the .js files
-            will appear in bazel-out/[arch]/bin/path/to/my/package/foo/*.js
+            so if your rule appears in path/to/my/package/BUILD.bazel and out_dir = "foo" then the .js files
+            will appear in bazel-out/[arch]/bin/path/to/my/package/foo/*.js.
+            By default the out_dir is '.', meaning the packages folder in bazel-out.
 
-        rootdir: a string specifying a subdirectory under the input package which should be consider the
-            root directory of all the input files.
+        declaration_dir: a string specifying a subdirectory under the bazel-out folder where generated declaration
+            outputs are written. Equivalent to the TypeScript --declarationDir option.
+            By default declarations are written to the out_dir.
 
         declaration: if the `declaration` bit is set in the tsconfig.
             Instructs Bazel to expect a `.d.ts` output for each `.ts` source.
@@ -377,6 +388,8 @@ def ts_project_macro(
             Instructs Bazel to expect a `.tsbuildinfo` output.
         emit_declaration_only: if the `emitDeclarationOnly` bit is set in the tsconfig.
             Instructs Bazel *not* to expect `.js` or `.js.map` outputs for `.ts` sources.
+
+        **kwargs: passed through to underlying rule, allows eg. visibility, tags
     """
 
     if srcs == None:
@@ -402,19 +415,22 @@ def ts_project_macro(
         )
         extra_deps.append("_validate_%s_options" % name)
 
+    typings_out_dir = declaration_dir if declaration_dir else out_dir
+
     ts_project(
         name = name,
         srcs = srcs,
         args = args,
         deps = deps + extra_deps,
         tsconfig = tsconfig,
         extends = extends,
-        outdir = outdir,
-        rootdir = rootdir,
-        js_outs = _out_paths(srcs, outdir, rootdir, ".js") if not emit_declaration_only else [],
-        map_outs = _out_paths(srcs, outdir, rootdir, ".js.map") if source_map and not emit_declaration_only else [],
-        typings_outs = _out_paths(srcs, outdir, rootdir, ".d.ts") if declaration or composite else [],
-        typing_maps_outs = _out_paths(srcs, outdir, rootdir, ".d.ts.map") if declaration_map else [],
+        declaration_dir = declaration_dir,
+        out_dir = out_dir,
+        root_dir = root_dir,
+        js_outs = _out_paths(srcs, out_dir, root_dir, ".js") if not emit_declaration_only else [],
+        map_outs = _out_paths(srcs, out_dir, root_dir, ".js.map") if source_map and not emit_declaration_only else [],
+        typings_outs = _out_paths(srcs, typings_out_dir, root_dir, ".d.ts") if declaration or composite else [],
+        typing_maps_outs = _out_paths(srcs, typings_out_dir, root_dir, ".d.ts.map") if declaration_map else [],
         buildinfo_out = tsconfig[:-5] + ".tsbuildinfo" if composite or incremental else None,
         tsc = tsc,
         **kwargs

packages/typescript/test/ts_project/declarationdir/BUILD.bazel

@@ -0,0 +1,36 @@
+load("@build_bazel_rules_nodejs//:index.bzl", "nodejs_test")
+load("//packages/typescript:index.bzl", "ts_project")
+
+# Ensure that subdir/a.ts produces outDir/a.js and outDir/a.d.ts
+SRCS = [
+    "subdir/a.ts",
+]
+
+ts_project(
+    name = "tsconfig",
+    srcs = SRCS,
+    declaration = True,
+    declaration_map = True,
+    out_dir = "out",
+    root_dir = "subdir",
+    source_map = True,
+)
+
+filegroup(
+    name = "types",
+    srcs = [":tsconfig"],
+    output_group = "types",
+)
+
+nodejs_test(
+    name = "test",
+    data = [
+        ":tsconfig",
+        ":types",
+    ],
+    entry_point = "verify.js",
+    templated_args = [
+        "$(locations :types)",
+        "$(locations :tsconfig)",
+    ],
+)

packages/typescript/test/ts_project/declarationdir/subdir/a.ts

@@ -0,0 +1 @@
+export const a: string = 'hello';

packages/typescript/test/ts_project/declarationdir/tsconfig.json

@@ -0,0 +1,8 @@
+{
+    "compilerOptions": {
+        "sourceMap": true,
+        "declaration": true,
+        "declarationMap": true,
+        "types": []
+    }
+}

packages/typescript/test/ts_project/declarationdir/verify.js

@@ -0,0 +1,8 @@
+const assert = require('assert');
+
+const types_files = process.argv.slice(2, 4);
+const code_files = process.argv.slice(4, 6);
+assert.ok(types_files.some(f => f.endsWith('declarationdir/out/a.d.ts')), 'Missing a.d.ts');
+assert.ok(types_files.some(f => f.endsWith('declarationdir/out/a.d.ts.map')), 'Missing a.d.ts.map');
+assert.ok(code_files.some(f => f.endsWith('declarationdir/out/a.js')), 'Missing a.js');
+assert.ok(code_files.some(f => f.endsWith('declarationdir/out/a.js.map')), 'Missing a.js.map');

packages/typescript/test/ts_project/declarationdir_with_value/BUILD.bazel

@@ -0,0 +1,37 @@
+load("@build_bazel_rules_nodejs//:index.bzl", "nodejs_test")
+load("//packages/typescript:index.bzl", "ts_project")
+
+# Ensure that subdir/a.ts produces outDir/a.js and declarationDir/a.d.ts
+SRCS = [
+    "subdir/a.ts",
+]
+
+ts_project(
+    name = "tsconfig",
+    srcs = SRCS,
+    declaration = True,
+    declaration_dir = "out/types",
+    declaration_map = True,
+    out_dir = "out/code",
+    root_dir = "subdir",
+    source_map = True,
+)
+
+filegroup(
+    name = "types",
+    srcs = [":tsconfig"],
+    output_group = "types",
+)
+
+nodejs_test(
+    name = "test",
+    data = [
+        ":tsconfig",
+        ":types",
+    ],
+    entry_point = "verify.js",
+    templated_args = [
+        "$(locations :types)",
+        "$(locations :tsconfig)",
+    ],
+)

packages/typescript/test/ts_project/declarationdir_with_value/subdir/a.ts

@@ -0,0 +1 @@
+export const a: string = 'hello';

packages/typescript/test/ts_project/declarationdir_with_value/tsconfig.json

@@ -0,0 +1,8 @@
+{
+    "compilerOptions": {
+        "sourceMap": true,
+        "declaration": true,
+        "declarationMap": true,
+        "types": []
+    }
+}

packages/typescript/test/ts_project/declarationdir_with_value/verify.js

@@ -0,0 +1,15 @@
+const assert = require('assert');
+
+const types_files = process.argv.slice(2, 4);
+const code_files = process.argv.slice(4, 6);
+assert.ok(
+    types_files.some(f => f.endsWith('declarationdir_with_value/out/types/a.d.ts')),
+    'Missing a.d.ts');
+assert.ok(
+    types_files.some(f => f.endsWith('declarationdir_with_value/out/types/a.d.ts.map')),
+    'Missing a.d.ts.map');
+assert.ok(
+    code_files.some(f => f.endsWith('declarationdir_with_value/out/code/a.js')), 'Missing a.js');
+assert.ok(
+    code_files.some(f => f.endsWith('declarationdir_with_value/out/code/a.js.map')),
+    'Missing a.js.map');

packages/typescript/test/ts_project/json/BUILD.bazel

@@ -10,7 +10,7 @@ SRCS = [
 ts_project(
     name = "tsconfig",
     srcs = SRCS,
-    outdir = "foobar",
+    out_dir = "foobar",
 )
 
 ts_project(

packages/typescript/test/ts_project/outdir/BUILD.bazel

@@ -10,7 +10,7 @@ load("//packages/typescript:index.bzl", "ts_project")
             format,
         ],
         # Write the output files to an extra nested directory
-        outdir = format,
+        out_dir = format,
         tsconfig = "tsconfig.json",
     )
     for format in [

packages/typescript/test/ts_project/rootdir_with_value/BUILD.bazel

@@ -9,7 +9,7 @@ SRCS = [
 ts_project(
     name = "tsconfig",
     srcs = SRCS,
-    rootdir = "subdir",
+    root_dir = "subdir",
 )
 
 nodejs_test(