refactor: simplify json output file declaration

Never predeclare these outputs, since in most cases we can't

packages/typescript/internal/ts_project.bzl

@@ -29,7 +29,6 @@ _ATTRS = {
 _OUTPUTS = {
     "buildinfo_out": attr.output(),
     "js_outs": attr.output_list(),
-    "json_outs": attr.output_list(),
     "map_outs": attr.output_list(),
     "typing_maps_outs": attr.output_list(),
     "typings_outs": attr.output_list(),
@@ -98,12 +97,20 @@ def _ts_project_impl(ctx):
     if ctx.attr.extends:
         inputs.extend(ctx.files.extends)
 
-    json_outs = ctx.outputs.json_outs
+    # 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.)
+    # 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:]))
+            for src in ctx.files.srcs
+            if src.basename.endswith(".json")
+        ]
+    else:
+        json_outs = []
 
-    # If there are no predeclared json_outs (probably bc of no .json or no outdir),
-    # let's try to search for them in srcs so we can declare them as output
-    if not json_outs:
-        json_outs = [ctx.actions.declare_file(src.basename, sibling = src) for src in ctx.files.srcs if src.basename.endswith(".json")]
     outputs = json_outs + ctx.outputs.js_outs + ctx.outputs.map_outs + ctx.outputs.typings_outs + ctx.outputs.typing_maps_outs
     if ctx.outputs.buildinfo_out:
         outputs.append(ctx.outputs.buildinfo_out)
@@ -398,9 +405,6 @@ def ts_project_macro(
         tsconfig = tsconfig,
         extends = extends,
         outdir = outdir,
-        # JSON files are special. They are output if outdir is set since tsc will
-        # copy them to outdir. Otherwise they are kind of both.
-        json_outs = [_join(outdir, f) for f in srcs if f.endswith(".json")] if outdir and not emit_declaration_only else [],
         js_outs = _out_paths(srcs, outdir, ".js") if not emit_declaration_only else [],
         map_outs = _out_paths(srcs, outdir, ".js.map") if source_map and not emit_declaration_only else [],
         typings_outs = _out_paths(srcs, outdir, ".d.ts") if declaration or composite else [],

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

@@ -1,7 +1,8 @@
-load("@build_bazel_rules_nodejs//:index.bzl", "generated_file_test", "nodejs_test")
+load("@build_bazel_rules_nodejs//:index.bzl", "nodejs_test")
 load("//packages/typescript:index.bzl", "ts_project")
 
-SRCS = glob(["**/*.ts*"]) + [
+SRCS = [
+    "subdir/a.ts",
     "subdir/foo.json",
     "bar.json",
 ]
@@ -18,25 +19,23 @@ ts_project(
     tsconfig = "tsconfig.json",
 )
 
-generated_file_test(
-    name = "test-subdir",
-    src = "foo.golden.json",
-    # Refers to the output from tsconfig ts_project above
-    generated = ":foobar/subdir/foo.json",
-)
-
-generated_file_test(
-    name = "test",
-    src = "bar.golden.json",
-    # Refers to the output from tsconfig ts_project above
-    generated = ":foobar/bar.json",
+# Test that we don't try to declare .json outputs when tsc isn't producing any JS
+ts_project(
+    name = "tsconfig-decl-only",
+    srcs = SRCS,
+    emit_declaration_only = True,
 )
 
 nodejs_test(
-    name = "test-no-outdir",
-    data = [":tsconfig-no-outdir"],
+    name = "test",
+    data = [
+        ":tsconfig",
+        ":tsconfig-decl-only",
+        ":tsconfig-no-outdir",
+    ],
     entry_point = "verify.js",
     templated_args = [
+        "$(locations :tsconfig)",
         "$(locations :tsconfig-no-outdir)",
     ],
 )

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

@@ -1,18 +1,8 @@
-const files = process.argv.slice(2)
-let barJson
-let subdirFooJson
-files.forEach(f => {
-  if (f.endsWith('bar.json')) {
-    barJson = f
-  } else if (f.endsWith('subdir/foo.json')) {
-    subdirFooJson = f
-  }
-})
-if (!barJson) {
-  console.error('Missing bar.json')
-  process.exitCode = 1
-}
-else if (!subdirFooJson) {
-  console.error('Missing subdir/foo.json')
-  process.exitCode = 1
-}
+const assert = require('assert');
+
+const files = process.argv.slice(2);
+assert.ok(files.some(f => f.endsWith('json/bar.json')), 'Missing bar.json');
+assert.ok(files.some(f => f.endsWith('json/subdir/foo.json')), 'Missing subdir/foo.json');
+assert.ok(files.some(f => f.endsWith('json/foobar/bar.json')), 'Missing outdir bar.json');
+assert.ok(
+    files.some(f => f.endsWith('json/foobar/subdir/foo.json')), 'Missing outdir subdir/foo.json');