Add ProblemExceptionTests

Author: malczuuu

src/test/java/io/github/malczuuu/problem4j/core/ProblemExceptionTests.java

@@ -0,0 +1,183 @@
+package io.github.malczuuu.problem4j.core;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+import org.junit.jupiter.api.Test;
+
+class ProblemExceptionTests {
+
+  @Test
+  void
+      givenProblemWithAllFields_whenCreatingException_thenMessageWithAllFieldsWithProperFormatting() {
+    Problem problem =
+        Problem.builder()
+            .type("https://example.com/error")
+            .title("Validation Error")
+            .detail("The request body is invalid")
+            .status(400)
+            .build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals(
+        "Validation Error: The request body is invalid (code: 400)", exception.getMessage());
+  }
+
+  @Test
+  void
+      givenProblemWithTitleAndDetail_whenCreatingException_thenMessageWithTitleAndDetailWithColon() {
+    Problem problem =
+        Problem.builder()
+            .title("Not Found")
+            .detail("The requested resource does not exist")
+            .build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Not Found: The requested resource does not exist", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithTitleAndStatus_whenCreatingException_thenMessageWithTitleAndStatus() {
+    Problem problem = Problem.builder().title("Unauthorized").status(401).build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Unauthorized (code: 401)", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithDetailAndStatus_whenCreatingException_thenMessageWithDetailAndStatus() {
+    Problem problem = Problem.builder().detail("Token has expired").status(401).build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Unauthorized: Token has expired (code: 401)", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithTitle_whenCreatingException_thenMessageWithTitle() {
+    Problem problem = Problem.builder().title("Internal Server Error").build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Internal Server Error", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithDetail_whenCreatingException_thenMessageWithDetail() {
+    Problem problem = Problem.builder().detail("Something went wrong").build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Something went wrong", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithStatus_whenCreatingException_thenMessageWithStatus() {
+    Problem problem = Problem.builder().status(500).build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Internal Server Error (code: 500)", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithNullTitleAndDetail_whenCreatingException_thenMessageIsNull() {
+    Problem problem = new Problem(null, null, 0, null, null, new Object[0]);
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertNull(exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithEmptyStringFields_whenCreatingException_thenMessageIsNull() {
+    Problem problem = Problem.builder().title("").detail("").build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertNull(exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithZeroStatus_whenCreatingException_thenStatusNotIncludedInMessage() {
+    Problem problem =
+        Problem.builder().title("Error").detail("Something happened").status(0).build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Error: Something happened", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithNegativeStatus_whenCreatingException_thenStatusIncludedInMessage() {
+    Problem problem = Problem.builder().title("Custom Error").status(-1).build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Custom Error (code: -1)", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithLargeStatus_whenCreatingException_thenStatusIncludedInMessage() {
+    Problem problem = Problem.builder().detail("Custom protocol error").status(999).build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Custom protocol error (code: 999)", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithWhitespaceTitle_whenCreatingException_thenTitleIncludedInMessage() {
+    Problem problem = Problem.builder().title("   ").detail("Error occurred").build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("   : Error occurred", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithSpecialCharacters_whenCreatingException_thenSpecialCharactersPreserved() {
+    Problem problem =
+        Problem.builder()
+            .title("Validation Error: Required Fields Missing")
+            .detail("Fields 'name' & 'email' are required (check docs)")
+            .status(422)
+            .build();
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals(
+        "Validation Error: Required Fields Missing: Fields 'name' & 'email' are required (check docs) (code: 422)",
+        exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithUnknownStatusCode_whenCreatingException_thenNoTitleResolutionOccurs() {
+    Problem problem = new Problem(null, null, 999, "Custom error", null, new Object[0]);
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Custom error (code: 999)", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithUnknownStatusCode_whenCreatingException_thenStatusShown() {
+    Problem problem = new Problem(null, null, 999, null, null, new Object[0]);
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("(code: 999)", exception.getMessage());
+  }
+
+  @Test
+  void givenProblemWithExplicitNullTitle_whenCreatingException_thenNoTitleInMessage() {
+    Problem problem = new Problem(null, null, 404, "Resource not found", null, new Object[0]);
+
+    ProblemException exception = new ProblemException(problem);
+
+    assertEquals("Resource not found (code: 404)", exception.getMessage());
+  }
+}