Cleanup and test cases for the failure modes with improved errors

pom.xml

@@ -48,11 +48,6 @@
             <artifactId>jsonassert</artifactId>
             <version>1.5.1</version>
         </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <version>5.10.2</version>
-        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-params</artifactId>

src/main/java/com/unitvectory/jsonparamunit/JsonNodeParamUnit.java

@@ -8,7 +8,6 @@
  */
 package com.unitvectory.jsonparamunit;
 
-import static org.junit.jupiter.api.Assertions.fail;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import org.json.JSONException;
@@ -71,20 +70,44 @@ public JsonNodeParamUnit(JsonParamUnitConfig config) {
      */
     public final void run(String filePath) {
 
+        if (filePath == null) {
+            throw new JsonParamError("The provided filePath is null.");
+        }
+
+        if (filePath.isEmpty()) {
+            throw new JsonParamError("The provided filePath is empty.");
+        }
+
+        Path path = Path.of(filePath);
+
+        // Check if the file exists
+
+        if (!Files.exists(path)) {
+            throw new JsonParamError("The provided filePath does not exist.");
+        }
+
+        // Check if the file is a directory
+
+        if (!Files.isRegularFile(path)) {
+            throw new JsonParamError("The provided filePath is not a regular file.");
+        }
+
+        // Parse the test JSON
+
         JsonNode rootNode = null;
         try {
             // Load the file path to string
-            String file = Files.readString(Path.of(filePath));
+            String file = Files.readString(path);
 
             // Parse the JSON
             rootNode = this.config.getMapper().readTree(file);
         } catch (Exception e) {
-            fail("Failed to parse JSON", e);
+            throw new JsonParamError("Failed to parse the JSON from the test file.", e);
         }
 
-        // THe input object
+        // The input object
         if (!rootNode.has("input")) {
-            fail("Input is missing");
+            throw new JsonParamError("The 'input' JSON Object is missing from the test file.");
         }
 
         JsonNode inputNode = rootNode.get("input");
@@ -94,7 +117,7 @@ public final void run(String filePath) {
 
         // The output object
         if (!rootNode.has("output")) {
-            fail("Output is missing");
+            throw new JsonParamError("The 'output' JSON Object is missing from the test file.");
         }
 
         JsonNode expectedOutputNode = rootNode.get("output");
@@ -104,8 +127,8 @@ public final void run(String filePath) {
         try {
             expectedOutput = this.config.getMapper().writeValueAsString(expectedOutputNode);
         } catch (JsonProcessingException e) {
-            fail("failed to encode expected output", e);
-            return;
+            throw new JsonParamError("The 'output' JSON Object could not be encoded as a string.",
+                    e);
         }
 
         // Process the input to produce the actual output
@@ -114,16 +137,16 @@ public final void run(String filePath) {
         try {
             actualOutput = this.config.getMapper().writeValueAsString(actualOutputNode);
         } catch (JsonProcessingException e) {
-            fail("failed to encode the actual output", e);
-            return;
+            throw new JsonParamError("The actual output could not be encoded as a string.", e);
         }
 
         // Assert the actual output matches the expected output
         // This is the actual purpose of the test case.
         try {
             JSONAssert.assertEquals(expectedOutput, actualOutput, this.config.isStrictOutput());
         } catch (JSONException e) {
-            fail("failed to assert the actual output matches the expected output", e);
+            throw new JsonParamError(
+                    "Failed to assert the actual output matches the expected output.", e);
         }
     }
 

src/main/java/com/unitvectory/jsonparamunit/JsonParamError.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v2.0 which accompanies this distribution and is available at
+ *
+ * https://www.eclipse.org/legal/epl-v20.html
+ */
+package com.unitvectory.jsonparamunit;
+
+/**
+ * The JsonParamError exception used to indicate an assertion failed.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+public class JsonParamError extends AssertionError {
+
+
+    /**
+     * Creates a new instance of the JsonParamError class.
+     * 
+     * @param message the message
+     */
+    public JsonParamError(String message) {
+        super(message);
+    }
+
+    /**
+     * Creates a new instance of the JsonParamError class.
+     * 
+     * @param message the message
+     * @param cause the cause
+     */
+    public JsonParamError(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    /**
+     * Creates a new instance of the JsonParamError class.
+     * 
+     * @param cause the cause
+     */
+    public JsonParamError(Throwable cause) {
+        super(cause);
+    }
+}

src/main/java/com/unitvectory/jsonparamunit/JsonStringParamUnit.java

@@ -8,7 +8,6 @@
  */
 package com.unitvectory.jsonparamunit;
 
-import static org.junit.jupiter.api.Assertions.fail;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
 
@@ -42,16 +41,15 @@ public final JsonNode process(JsonNode input, String context) {
         try {
             inputString = this.getConfig().getMapper().writeValueAsString(input);
         } catch (JsonProcessingException e) {
-            fail("failed to encode input as JsonNode", e);
+            throw new JsonParamError("Failed to encode input as String.", e);
         }
 
         String outputString = process(inputString, context);
 
         try {
             return this.getConfig().getMapper().readTree(outputString);
         } catch (JsonProcessingException e) {
-            fail("failed to encode ouput as JsonNode", e);
-            return null;
+            throw new JsonParamError("Failed to decode output as JsonNode.", e);
         }
     }
 

src/test/java/com/unitvectory/jsonparamunit/FailuresTest.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v2.0 which accompanies this distribution and is available at
+ *
+ * https://www.eclipse.org/legal/epl-v20.html
+ */
+package com.unitvectory.jsonparamunit;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import java.io.File;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.unitvectory.fileparamunit.ListFileSource;
+
+/**
+ * Test cases for testing the failures by intentionally misconfiguring the test case environment and
+ * asserting the correct exception is thrown to describe the failure.
+ * 
+ * @author Jared Hatfield (UnitVectorY Labs)
+ */
+public class FailuresTest extends JsonNodeParamUnit {
+
+    @Test
+    public void filePathNullTest() {
+        JsonParamError exception = assertThrows(JsonParamError.class, () -> {
+            run(null);
+        });
+
+        assertEquals("The provided filePath is null.", exception.getMessage());
+    }
+
+    @Test
+    public void filePathEmptyTest() {
+        JsonParamError exception = assertThrows(JsonParamError.class, () -> {
+            run("");
+        });
+
+        assertEquals("The provided filePath is empty.", exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ListFileSource(resources = "/failures/badjson", fileExtension = ".json")
+    public void fileNotExistTest(String file) {
+        JsonParamError exception = assertThrows(JsonParamError.class, () -> {
+            // Changing the file path it won't exist
+            run(file + "x");
+        });
+
+        assertEquals("The provided filePath does not exist.", exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ListFileSource(resources = "/failures/badjson", fileExtension = ".json")
+    public void fileIsDirectoryTest(String file) {
+        // For this test instead of the file we are getting the directory it is in which will fail
+        String directory = new File(file).getParent();
+        JsonParamError exception = assertThrows(JsonParamError.class, () -> {
+            // Changing the file path it won't exist
+            run(directory);
+        });
+
+        assertEquals("The provided filePath is not a regular file.", exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ListFileSource(resources = "/failures/badjson", fileExtension = ".json")
+    public void badJsonTest(String file) {
+        JsonParamError exception = assertThrows(JsonParamError.class, () -> {
+            // Changing the file path it won't exist
+            run(file);
+        });
+
+        assertEquals("Failed to parse the JSON from the test file.", exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ListFileSource(resources = "/failures/noinput", fileExtension = ".json")
+    public void noInputTest(String file) {
+        JsonParamError exception = assertThrows(JsonParamError.class, () -> {
+            run(file);
+        });
+
+        assertEquals("The 'input' JSON Object is missing from the test file.",
+                exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ListFileSource(resources = "/failures/nooutput", fileExtension = ".json")
+    public void noOutputTest(String file) {
+        JsonParamError exception = assertThrows(JsonParamError.class, () -> {
+            run(file);
+        });
+
+        assertEquals("The 'output' JSON Object is missing from the test file.",
+                exception.getMessage());
+    }
+
+    @Override
+    public JsonNode process(JsonNode input, String context) {
+        return this.getConfig().getMapper().createObjectNode();
+    }
+
+}

src/test/resources/failures/badjson/file.json

@@ -0,0 +1 @@
+{

src/test/resources/failures/noinput/file.json

@@ -0,0 +1,6 @@
+{
+  "context": "context",
+  "output": {
+    "foo": "bar"
+  }
+}

src/test/resources/failures/nooutput/file.json

@@ -0,0 +1,6 @@
+{
+  "input": {
+    "foo": "bar"
+  },
+  "context": "myContext"
+}