Fix NPE and contract to pass the variable

Author: eirnym

lib/src/ktlint/java/com/diffplug/spotless/glue/ktlint/KtlintFormatterFunc.java

@@ -15,14 +15,14 @@
  */
 package com.diffplug.spotless.glue.ktlint;
 
-import com.diffplug.spotless.FileSignature;
-import com.diffplug.spotless.FormatterFunc;
-import com.diffplug.spotless.glue.ktlint.compat.*;
+import java.io.File;
+import java.util.Map;
 
 import org.jetbrains.annotations.NotNull;
 
-import java.io.File;
-import java.util.Map;
+import com.diffplug.spotless.FileSignature;
+import com.diffplug.spotless.FormatterFunc;
+import com.diffplug.spotless.glue.ktlint.compat.*;
 
 public class KtlintFormatterFunc implements FormatterFunc.NeedsFile {
 
@@ -35,7 +35,7 @@ public class KtlintFormatterFunc implements FormatterFunc.NeedsFile {
 	private final Map<String, Object> editorConfigOverrideMap;
 
 	public KtlintFormatterFunc(String version, boolean isScript, boolean useExperimental, FileSignature editorConfigPath, Map<String, String> userData,
-							   Map<String, Object> editorConfigOverrideMap) {
+			Map<String, Object> editorConfigOverrideMap) {
 		int minorVersion = Integer.parseInt(version.split("\\.")[1]);
 		if (minorVersion >= 48) {
 			// ExperimentalParams lost two constructor arguments, EditorConfigProperty moved to its own class
@@ -68,6 +68,11 @@ public KtlintFormatterFunc(String version, boolean isScript, boolean useExperime
 
 	@Override
 	public String applyWithFile(String unix, File file) {
-		return adapter.format(unix, file.getName(), isScript, useExperimental, editorConfigPath.getOnlyFile().getAbsolutePath(), userData, editorConfigOverrideMap);
+
+		String absoluteEditorConfigPath = null;
+		if (editorConfigPath != null) {
+			absoluteEditorConfigPath = editorConfigPath.getOnlyFile().getAbsolutePath();
+		}
+		return adapter.format(unix, file.getName(), isScript, useExperimental, absoluteEditorConfigPath, userData, editorConfigOverrideMap);
 	}
 }

lib/src/main/java/com/diffplug/spotless/kotlin/KtLintStep.java

@@ -59,7 +59,7 @@ public static FormatterStep createForScript(String version, Provisioner provisio
 	}
 
 	public static FormatterStep createForScript(String version, Provisioner provisioner, boolean useExperimental,
-			Map<String, String> userData, Map<String, Object> editorConfigOverride) {
+			FileSignature editorConfigPath, Map<String, String> userData, Map<String, Object> editorConfigOverride) {
 		return create(version, provisioner, true, useExperimental, userData, editorConfigOverride);
 	}
 
@@ -119,7 +119,7 @@ FormatterFunc createFormat() throws Exception {
 			final ClassLoader classLoader = jarState.getClassLoader();
 			Class<?> formatterFunc = classLoader.loadClass("com.diffplug.spotless.glue.ktlint.KtlintFormatterFunc");
 			Constructor<?> constructor = formatterFunc.getConstructor(
-					String.class, boolean.class, boolean.class, String.class, Map.class, Map.class);
+					String.class, boolean.class, boolean.class, FileSignature.class, Map.class, Map.class);
 			return (FormatterFunc.NeedsFile) constructor.newInstance(version, isScript, useExperimental, editorConfigPath, userData, editorConfigOverride);
 		}
 	}