lintify GsonStep (tests only)

Author: nedtwigg

lib/src/gson/java/com/diffplug/spotless/glue/gson/GsonFormatterFunc.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2023 DiffPlug
+ * Copyright 2023-2024 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,7 +32,7 @@
 
 public class GsonFormatterFunc implements FormatterFunc {
 
-	private static final String FAILED_TO_PARSE_ERROR_MESSAGE = "Unable to format JSON";
+	private static final String FAILED_TO_PARSE_ERROR_MESSAGE = "Unable to parse JSON";
 
 	private final Gson gson;
 	private final GsonConfig gsonConfig;
@@ -56,7 +56,7 @@ public String apply(String inputString) {
 		} else {
 			JsonElement jsonElement = gson.fromJson(inputString, JsonElement.class);
 			if (jsonElement == null) {
-				throw new AssertionError(FAILED_TO_PARSE_ERROR_MESSAGE);
+				throw new IllegalArgumentException(FAILED_TO_PARSE_ERROR_MESSAGE);
 			}
 			if (gsonConfig.isSortByKeys()) {
 				jsonElement = sortByKeys(jsonElement);

testlib/src/test/java/com/diffplug/spotless/json/gson/GsonStepTest.java

@@ -17,9 +17,6 @@
 
 import static com.diffplug.spotless.json.gson.GsonStep.DEFAULT_VERSION;
 
-import java.io.File;
-
-import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import com.diffplug.spotless.FormatterStep;
@@ -42,12 +39,32 @@ void handlesObjectWithNull() {
 
 	@Test
 	void handlesInvalidJson() {
-		getStepHarness().testResourceExceptionMsg("json/invalidJsonBefore.json").isEqualTo("End of input at line 3 column 1 path $.a");
+		getStepHarness().expectLintsOfResource("json/invalidJsonBefore.json").toBe("L3 gson(com.google.gson.JsonSyntaxException) java.io.EOFException: End of input at line 3 column 1 path $.a",
+				"\tat com.google.gson.Gson.fromJson(Gson.java:1370)",
+				"\tat com.google.gson.Gson.fromJson(Gson.java:1262)",
+				"\tat com.google.gson.Gson.fromJson(Gson.java:1171)",
+				"\tat com.google.gson.Gson.fromJson(Gson.java:1107)",
+				"\tat com.diffplug.spotless.glue.gson.GsonFormatterFunc.apply(GsonFormatterFunc.java:57)",
+				"\tat com.diffplug.spotless.FormatterFunc.apply(FormatterFunc.java:33)",
+				"\tat com.diffplug.spotless.FormatterStepEqualityOnStateSerialization.format(FormatterStepEqualityOnStateSerialization.java:49)",
+				"\tat com.diffplug.spotless.LintState.of(LintState.java:141)",
+				"\tat com.diffplug.spotless.StepHarness.expectLintsOf(StepHarness.java:96)",
+				"(... and more)");
 	}
 
 	@Test
 	void handlesNotJson() {
-		getStepHarness().testResourceExceptionMsg("json/notJsonBefore.json").isEqualTo("Unable to format JSON");
+		getStepHarness().expectLintsOfResource("json/notJsonBefore.json").toBe("LINE_UNDEFINED gson(java.lang.IllegalArgumentException) Unable to parse JSON",
+				"\tat com.diffplug.spotless.glue.gson.GsonFormatterFunc.apply(GsonFormatterFunc.java:59)",
+				"\tat com.diffplug.spotless.FormatterFunc.apply(FormatterFunc.java:33)",
+				"\tat com.diffplug.spotless.FormatterStepEqualityOnStateSerialization.format(FormatterStepEqualityOnStateSerialization.java:49)",
+				"\tat com.diffplug.spotless.LintState.of(LintState.java:141)",
+				"\tat com.diffplug.spotless.StepHarness.expectLintsOf(StepHarness.java:96)",
+				"\tat com.diffplug.spotless.StepHarness.expectLintsOfResource(StepHarness.java:92)",
+				"\tat com.diffplug.spotless.json.gson.GsonStepTest.handlesNotJson(GsonStepTest.java:57)",
+				"\tat java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)",
+				"\tat java.base/java.lang.reflect.Method.invoke(Method.java:580)",
+				"(... and more)");
 	}
 
 	@Test
@@ -79,10 +96,18 @@ void writesRawHtmlWhenHtmlEscapeDisabled() {
 
 	@Test
 	void handlesVersionIncompatibility() {
-		FormatterStep step = GsonStep.create(new GsonConfig(false, false, INDENT, "1.7"), TestProvisioner.mavenCentral());
-		Assertions.assertThatThrownBy(() -> step.format("", new File("")))
-				.isInstanceOf(IllegalStateException.class)
-				.hasMessage("There was a problem interacting with Gson; maybe you set an incompatible version?");
+		StepHarness.forStep(GsonStep.create(new GsonConfig(false, false, INDENT, "1.7"), TestProvisioner.mavenCentral()))
+				.expectLintsOf("").toBe("LINE_UNDEFINED gson(java.lang.IllegalStateException) There was a problem interacting with Gson; maybe you set an incompatible version?",
+						"\tat com.diffplug.spotless.json.gson.GsonStep$State.toFormatter(GsonStep.java:73)",
+						"\tat com.diffplug.spotless.FormatterStepSerializationRoundtrip.stateToFormatter(FormatterStepSerializationRoundtrip.java:64)",
+						"\tat com.diffplug.spotless.FormatterStepEqualityOnStateSerialization.format(FormatterStepEqualityOnStateSerialization.java:47)",
+						"\tat com.diffplug.spotless.LintState.of(LintState.java:141)",
+						"\tat com.diffplug.spotless.StepHarness.expectLintsOf(StepHarness.java:96)",
+						"\tat com.diffplug.spotless.json.gson.GsonStepTest.handlesVersionIncompatibility(GsonStepTest.java:100)",
+						"\tat java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)",
+						"\tat java.base/java.lang.reflect.Method.invoke(Method.java:580)",
+						"\tat org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:766)",
+						"(... and more)");
 	}
 
 	@Override