feat: transpile using --noCheck when isolatedDeclarations

Ref #88
Ref #374

examples/isolated_declarations/backend/BUILD.bazel

@@ -4,6 +4,7 @@ load("@aspect_rules_ts//ts:defs.bzl", "ts_project")
 ts_project(
     name = "backend",
     declaration = True,
+    isolated_declarations = True,
     tsconfig = "//examples/isolated_declarations:tsconfig",
     deps = ["//examples/isolated_declarations/core"],
 )

examples/isolated_declarations/core/BUILD.bazel

@@ -3,6 +3,7 @@ load("@aspect_rules_ts//ts:defs.bzl", "ts_project")
 ts_project(
     name = "core",
     declaration = True,
+    isolated_declarations = True,
     tsconfig = "//examples/isolated_declarations:tsconfig",
     visibility = ["//examples/isolated_declarations:__subpackages__"],
 )

examples/isolated_declarations/core/index.ts

@@ -12,3 +12,9 @@ type UnionToIntersection<U> = (U extends any ? (k: U) => void : never) extends (
 type UnionType = { a: number } | { b: string } | { c: boolean }
 
 export type IntersectionType = UnionToIntersection<UnionType>
+
+export const MyIntersectingValue: IntersectionType = {
+    a: 1,
+    b: '2',
+    c: true,
+}

examples/isolated_declarations/frontend/BUILD.bazel

@@ -5,6 +5,7 @@ ts_project(
     tsconfig = {
         "compilerOptions": {
             "declaration": True,
+            "isolatedDeclarations": True,
         },
     },
     deps = ["//examples/isolated_declarations/core"],

examples/isolated_declarations/frontend/index.ts

@@ -1,4 +1,5 @@
 import type { IntersectionType } from '../core'
+import { MyIntersectingValue } from '../core'
 
 // Example object of IntersectionType
 const myObject: IntersectionType = {
@@ -7,4 +8,6 @@ const myObject: IntersectionType = {
     c: true,
 }
 
-console.log(myObject)
+const otherObject = MyIntersectingValue
+
+console.log(myObject, otherObject, myObject === otherObject)

ts/defs.bzl

@@ -40,6 +40,7 @@ def ts_project(
         assets = [],
         extends = None,
         allow_js = False,
+        isolated_declarations = None,
         declaration = False,
         source_map = False,
         declaration_map = False,
@@ -152,6 +153,10 @@ def ts_project(
             See https://www.typescriptlang.org/docs/handbook/compiler-options.html#compiler-options
             Typically useful arguments for debugging are `--listFiles` and `--listEmittedFiles`.
 
+        isolated_declarations: Whether to enforce that declaration output (.d.ts file) can be produced for a
+            single source file at a time. Requires some additional explicit types on exported symbols.
+            See https://www.typescriptlang.org/docs/handbook/release-notes/typescript-5-5.html#isolated-declarations
+
         transpiler: A custom transpiler tool to run that produces the JavaScript outputs instead of `tsc`.
 
             Under `--@aspect_rules_ts//ts:default_to_tsc_transpiler`, the default is to use `tsc` to produce
@@ -280,6 +285,14 @@ def ts_project(
         allow_js = compiler_options.setdefault("allowJs", allow_js)
         if resolve_json_module != None:
             resolve_json_module = compiler_options.setdefault("resolveJsonModule", resolve_json_module)
+        if isolated_declarations != None:
+            isolated_declarations = compiler_options.setdefault("isolatedDeclarations", isolated_declarations)
+
+        # Options not set by default due to tsc version compatibility
+        if "isolatedDeclarations" in compiler_options.keys():
+            isolated_declarations = compiler_options.get("isolatedDeclarations")
+        elif isolated_declarations != None:
+            compiler_options["isolatedDeclarations"] = isolated_declarations
 
         # These options are always passed on the tsc command line so don't include them
         # in the tsconfig. At best they're redundant, but at worst we'll have a conflict
@@ -321,8 +334,9 @@ def ts_project(
     else:
         # To stitch together a tree of ts_project where transpiler is a separate rule,
         # we have to produce a few targets
-        tsc_target_name = "%s_typings" % name
+        tsc_target_name = "%s_tsc" % name
         transpile_target_name = "%s_transpile" % name
+        typings_target_name = "%s_typings" % name
         typecheck_target_name = "%s_typecheck" % name
         test_target_name = "%s_typecheck_test" % name
 
@@ -342,14 +356,31 @@ def ts_project(
         else:
             fail("transpiler attribute should be a rule/macro or a skylib partial. Got " + type(transpiler))
 
-        # Users should build this target to get a failed build when typechecking fails
-        native.filegroup(
-            name = typecheck_target_name,
-            srcs = [tsc_target_name],
-            # This causes the types to be produced, which in turn triggers the tsc action to typecheck
-            output_group = "types",
-            **common_kwargs
-        )
+        if isolated_declarations:
+            # Users should build this target to get a failed build when typechecking fails
+            native.filegroup(
+                name = typecheck_target_name,
+                srcs = [tsc_target_name],
+                output_group = "typecheck",
+                **common_kwargs
+            )
+
+            native.filegroup(
+                name = typings_target_name,
+                srcs = [tsc_target_name],
+                # This causes the types to be produced, which in turn triggers the tsc action to typecheck
+                output_group = "types",
+                **common_kwargs
+            )
+        else:
+            # Users should build this target to get a failed build when typechecking fails
+            native.filegroup(
+                name = typecheck_target_name,
+                srcs = [tsc_target_name],
+                # This causes the types to be produced, which in turn triggers the tsc action to typecheck
+                output_group = "types",
+                **common_kwargs
+            )
 
         # Ensures the typecheck target gets built under `bazel test --build_tests_only`
         build_test(
@@ -389,6 +420,7 @@ def ts_project(
         incremental = incremental,
         preserve_jsx = preserve_jsx,
         composite = composite,
+        isolated_declarations = isolated_declarations,
         declaration = declaration,
         declaration_dir = declaration_dir,
         source_map = source_map,

ts/private/ts_lib.bzl

@@ -108,6 +108,9 @@ COMPILER_OPTION_ATTRS = {
     "composite": attr.bool(
         doc = "https://www.typescriptlang.org/tsconfig#composite",
     ),
+    "isolated_declarations": attr.bool(
+        doc = "https://www.typescriptlang.org/tsconfig/#isolatedDeclarations",
+    ),
     "declaration": attr.bool(
         doc = "https://www.typescriptlang.org/tsconfig#declaration",
     ),