From 2dcee1036482c240b775403d6ff153f9a4f791c8 Mon Sep 17 00:00:00 2001
From: orangain <orangain@gmail.com>
Date: Sun, 5 Feb 2023 23:38:50 +0900
Subject: [PATCH] Fix match of empty object literal

---
 .../pattern/ObjectLiteralPatternNode.java     |  4 ++
 .../jsonmatch/EmptyObjectLiteralTest.kt       | 50 +++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 src/test/kotlin/io/github/orangain/jsonmatch/EmptyObjectLiteralTest.kt

diff --git a/src/main/java/io/github/orangain/jsonmatch/pattern/ObjectLiteralPatternNode.java b/src/main/java/io/github/orangain/jsonmatch/pattern/ObjectLiteralPatternNode.java
index 5dfd8ba..d79c377 100644
--- a/src/main/java/io/github/orangain/jsonmatch/pattern/ObjectLiteralPatternNode.java
+++ b/src/main/java/io/github/orangain/jsonmatch/pattern/ObjectLiteralPatternNode.java
@@ -23,6 +23,10 @@ public ObjectLiteralPatternNode(@NotNull String expected, @NotNull Map<String, J
     @NotNull
     @Override
     public Optional<JsonMatchErrorDetail> matches(@NotNull JsonPath path, @NotNull JsonNode actualNode) {
+        if (!actualNode.isObject()) {
+            String reason = "not a json object";
+            return Optional.of(error(path, actualNode, reason));
+        }
         Set<String> actualFieldNames = new HashSet<>();
         actualNode.fieldNames().forEachRemaining(actualFieldNames::add);
 
diff --git a/src/test/kotlin/io/github/orangain/jsonmatch/EmptyObjectLiteralTest.kt b/src/test/kotlin/io/github/orangain/jsonmatch/EmptyObjectLiteralTest.kt
new file mode 100644
index 0000000..9cedafe
--- /dev/null
+++ b/src/test/kotlin/io/github/orangain/jsonmatch/EmptyObjectLiteralTest.kt
@@ -0,0 +1,50 @@
+package io.github.orangain.jsonmatch
+
+import org.assertj.core.api.Assertions
+import org.junit.Test
+
+class EmptyObjectLiteralTest {
+    val patternJson = "{}"
+
+    @Test
+    fun matchEmptyObject() {
+        // language=JSON
+        JsonStringAssert.assertThat("{}").jsonMatches(patternJson)
+    }
+
+    @Test
+    fun doesNotMatchArray() {
+        Assertions.assertThatThrownBy {
+            // language=JSON
+            JsonStringAssert.assertThat("[]").jsonMatches(patternJson)
+        }.isInstanceOf(AssertionError::class.java)
+            .hasMessageContaining("""path: $, actual: [], expected: {}, reason: not a json object""")
+    }
+
+    @Test
+    fun doesNotMatchNumber() {
+        Assertions.assertThatThrownBy {
+            // language=JSON
+            JsonStringAssert.assertThat("0").jsonMatches(patternJson)
+        }.isInstanceOf(AssertionError::class.java)
+            .hasMessageContaining("""path: $, actual: 0, expected: {}, reason: not a json object""")
+    }
+
+    @Test
+    fun doesNotMatchString() {
+        Assertions.assertThatThrownBy {
+            // language=JSON
+            JsonStringAssert.assertThat("\"foo\"").jsonMatches(patternJson)
+        }.isInstanceOf(AssertionError::class.java)
+            .hasMessageContaining("""path: $, actual: "foo", expected: {}, reason: not a json object""")
+    }
+
+    @Test
+    fun doesNotMatchNull() {
+        Assertions.assertThatThrownBy {
+            // language=JSON
+            JsonStringAssert.assertThat("null").jsonMatches(patternJson)
+        }.isInstanceOf(AssertionError::class.java)
+            .hasMessageContaining("""path: $, actual: null, expected: {}, reason: not a json object""")
+    }
+}
\ No newline at end of file