diff --git a/src/test-suite/tests/contains.json b/src/test-suite/tests/contains.json
index 3bf0d7c..e503c87 100644
--- a/src/test-suite/tests/contains.json
+++ b/src/test-suite/tests/contains.json
@@ -96,6 +96,88 @@
       },
       "instance": ["foo", 42],
       "errors": []
+    },
+    {
+      "description": "contains fails due to too many matching items with success explanations",
+      "compatibility": "2019",
+      "schema": {
+        "contains": { "type": "string" },
+        "maxContains": 1
+      },
+      "instance": [42, "foo", "bar"],
+      "errors": [
+        {
+          "messageId": "contains-exact-message",
+          "messageParams": {
+            "minContains": 1,
+            "maxContains": 1
+          },
+          "instanceLocation": "#",
+          "schemaLocations": ["#/contains", "#/maxContains"],
+          "alternatives": [
+            [
+              {
+                "messageId": "type-success",
+                "messageParams": {
+                  "actualType": "string"
+                },
+                "instanceLocation": "#/1",
+                "schemaLocations": ["#/contains/type"]
+              }
+            ],
+            [
+              {
+                "messageId": "type-success",
+                "messageParams": {
+                  "actualType": "string"
+                },
+                "instanceLocation": "#/2",
+                "schemaLocations": ["#/contains/type"]
+              }
+            ]
+          ]
+        },
+        {
+          "description": "contains fails with multiple object matches",
+          "compatibility": "2019",
+          "schema": {
+            "contains": {
+              "required": ["a"]
+            },
+            "maxContains": 1
+          },
+          "instance": [{ "a": 1 }, { "a": 2 }],
+          "errors": [
+            {
+              "messageId": "contains-exact-message",
+              "messageParams": {
+                "minContains": 1,
+                "maxContains": 1
+              },
+              "instanceLocation": "#",
+              "schemaLocations": ["#/contains", "#/maxContains"],
+              "alternatives": [
+                [
+                  {
+                    "messageId": "required-success",
+                    "messageParams": { "property": "a" },
+                    "instanceLocation": "#/0",
+                    "schemaLocations": ["#/contains/required"]
+                  }
+                ],
+                [
+                  {
+                    "messageId": "required-success",
+                    "messageParams": { "property": "a" },
+                    "instanceLocation": "#/1",
+                    "schemaLocations": ["#/contains/required"]
+                  }
+                ]
+              ]
+            }
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/src/test-suite/tests/not.json b/src/test-suite/tests/not.json
index 154b397..8a676a7 100644
--- a/src/test-suite/tests/not.json
+++ b/src/test-suite/tests/not.json
@@ -24,6 +24,58 @@
       },
       "instance": "foo",
       "errors": []
+    },
+    {
+      "description": "not fails with success explanation",
+      "schema": {
+        "not": { "pattern": "^a" }
+      },
+      "instance": "apple",
+      "errors": [
+        {
+          "messageId": "not-message",
+          "instanceLocation": "#",
+          "schemaLocations": ["#/not"],
+          "alternatives": [
+            [
+              {
+                "messageId": "pattern-success",
+                "messageParams": {
+                  "pattern": "^a"
+                },
+                "instanceLocation": "#",
+                "schemaLocations": ["#/not/pattern"]
+              }
+            ]
+          ]
+        }
+      ]
+    },
+    {
+      "description": "not with nested schema producing a match",
+      "schema": {
+        "not": {
+          "required": ["a"]
+        }
+      },
+      "instance": { "a": 1 },
+      "errors": [
+        {
+          "messageId": "not-message",
+          "instanceLocation": "#",
+          "schemaLocations": ["#/not"],
+          "alternatives": [
+            [
+              {
+                "messageId": "required-success",
+                "messageParams": { "property": "a" },
+                "instanceLocation": "#",
+                "schemaLocations": ["#/not/required"]
+              }
+            ]
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/src/test-suite/tests/oneOf.json b/src/test-suite/tests/oneOf.json
index 658af9d..cd7ea10 100644
--- a/src/test-suite/tests/oneOf.json
+++ b/src/test-suite/tests/oneOf.json
@@ -6,10 +6,7 @@
     {
       "description": "oneOf",
       "schema": {
-        "oneOf": [
-          { "type": "string" },
-          { "type": "number" }
-        ]
+        "oneOf": [{ "type": "string" }, { "type": "number" }]
       },
       "instance": null,
       "errors": [
@@ -46,10 +43,7 @@
     {
       "description": "oneOf more than one match",
       "schema": {
-        "oneOf": [
-          { "type": "integer" },
-          { "type": "number" }
-        ]
+        "oneOf": [{ "type": "integer" }, { "type": "number" }]
       },
       "instance": 1,
       "errors": [
@@ -66,13 +60,126 @@
     {
       "description": "oneOf pass",
       "schema": {
-        "oneOf": [
-          { "type": "string" },
-          { "type": "number" }
-        ]
+        "oneOf": [{ "type": "string" }, { "type": "number" }]
       },
       "instance": 42,
       "errors": []
+    },
+    {
+      "description": "oneOf more than one match with success explanations",
+      "schema": {
+        "oneOf": [{ "type": "integer" }, { "type": "number" }]
+      },
+      "instance": 66,
+      "errors": [
+        {
+          "messageId": "oneOf-message",
+          "messageParams": { "matchCount": 2 },
+          "alternatives": [
+            [
+              {
+                "messageId": "type-success",
+                "messageParams": {
+                  "actualType": "integer"
+                },
+                "instanceLocation": "#",
+                "schemaLocations": ["#/oneOf/0/type"]
+              }
+            ],
+            [
+              {
+                "messageId": "type-success",
+                "messageParams": {
+                  "actualType": "number"
+                },
+                "instanceLocation": "#",
+                "schemaLocations": ["#/oneOf/1/type"]
+              }
+            ]
+          ],
+          "instanceLocation": "#",
+          "schemaLocations": ["#/oneOf"]
+        }
+      ]
+    },
+    {
+      "description": "oneOf more than one match with failed alternatives ignored",
+      "schema": {
+        "oneOf": [
+          { "required": ["a"] },
+          { "required": ["b"] },
+          { "required": ["c"] }
+        ]
+      },
+      "instance": { "a": 1, "b": 2 },
+      "errors": [
+        {
+          "messageId": "oneOf-message",
+          "messageParams": { "matchCount": 2 },
+          "alternatives": [
+            [
+              {
+                "messageId": "required-success", 
+                "messageParams": { 
+                  "property": "a"
+                },  
+                "instanceLocation": "#",
+                "schemaLocations": ["#/oneOf/0/required"]
+              }
+            ],
+            [
+              {
+                "messageId": "required-success",
+                "messageParams": {
+                  "property": "b"
+                },
+                "instanceLocation": "#",
+                "schemaLocations": ["#/oneOf/1/required"]
+              }
+            ]
+          ],
+          "instanceLocation": "#",
+          "schemaLocations": ["#/oneOf"]
+        }
+      ]
+    },
+    {
+      "description": "nested oneOf producing multiple matches in inner oneOf",
+      "schema": {
+        "oneOf": [
+          {
+            "oneOf": [{ "required": ["a"] }, { "required": ["b"] }]
+          },
+          { "required": ["c"] }
+        ]
+      },
+      "instance": { "a": 1, "b": 2 },
+      "errors": [
+        {
+          "messageId": "oneOf-message",
+          "messageParams": { "matchCount": 2 },
+          "instanceLocation": "#",
+          "schemaLocations": ["#/oneOf/0/oneOf"],
+          "alternatives": [
+            [
+              {
+                "messageId": "required-success",
+                "messageParams": { "property": "a" },
+                "instanceLocation": "#",
+                "schemaLocations": ["#/oneOf/0/oneOf/0/required"]
+              }
+            ],
+            [
+              {
+                "messageId": "required-success",
+                "messageParams": { "property": "b" },
+                "instanceLocation": "#",
+                "schemaLocations": ["#/oneOf/0/oneOf/1/required"]
+              }
+            ]
+          ]
+        }
+      ]
     }
   ]
 }