Introduce "minimal" test reporter (#1563)

pkl-commons-cli/src/main/kotlin/org/pkl/commons/cli/CliTestOptions.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,4 +22,5 @@ class CliTestOptions(
   val overwrite: Boolean = false,
   val junitAggregateReports: Boolean = false,
   val junitAggregateSuiteName: String = "pkl-tests",
+  val reporter: TestReporter = TestReporter.SPEC,
 )

pkl-commons-cli/src/main/kotlin/org/pkl/commons/cli/TestReporter.kt

@@ -0,0 +1,21 @@
+/*
+ * Copyright © 2026 Apple Inc. and the Pkl project authors. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.pkl.commons.cli
+
+enum class TestReporter {
+  SPEC,
+  MINIMAL,
+}

pkl-commons-cli/src/main/kotlin/org/pkl/commons/cli/commands/TestOptions.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,9 +19,11 @@ import com.github.ajalt.clikt.parameters.groups.OptionGroup
 import com.github.ajalt.clikt.parameters.options.default
 import com.github.ajalt.clikt.parameters.options.flag
 import com.github.ajalt.clikt.parameters.options.option
+import com.github.ajalt.clikt.parameters.types.enum
 import com.github.ajalt.clikt.parameters.types.path
 import java.nio.file.Path
 import org.pkl.commons.cli.CliTestOptions
+import org.pkl.commons.cli.TestReporter
 
 class TestOptions : OptionGroup() {
   private val junitReportDir: Path? by
@@ -51,7 +53,19 @@ class TestOptions : OptionGroup() {
   private val overwrite: Boolean by
     option(names = arrayOf("--overwrite"), help = "Force generation of expected examples.").flag()
 
+  private val reporter: TestReporter by
+    option(names = arrayOf("--test-reporter"), help = "Which test reporter to use for CLI output.")
+      .enum<TestReporter> { it.name.lowercase() }
+      .single()
+      .default(TestReporter.SPEC)
+
   val cliTestOptions: CliTestOptions by lazy {
-    CliTestOptions(junitReportDir, overwrite, junitAggregateReports, junitAggregateSuiteName)
+    CliTestOptions(
+      junitReportDir,
+      overwrite,
+      junitAggregateReports,
+      junitAggregateSuiteName,
+      reporter,
+    )
   }
 }