diff --git a/tests/Composer/Test/Fixtures/installer/broken-deps-do-not-replace.test b/tests/Composer/Test/Fixtures/installer/broken-deps-do-not-replace.test
new file mode 100644
index 000000000000..c626db198d7f
--- /dev/null
+++ b/tests/Composer/Test/Fixtures/installer/broken-deps-do-not-replace.test
@@ -0,0 +1,25 @@
+--TEST--
+Broken dependencies should not lead to a replacer being installed which is not mentioned by name
+--COMPOSER--
+{
+    "repositories": [
+        {
+            "type": "package",
+            "package": [
+                { "name": "a/a", "version": "1.0.0" },
+                { "name": "b/b", "version": "1.0.0", "require": {"c/c": "1.*"} },
+                { "name": "c/c", "version": "1.0.0", "replace": {"a/a": "1.0.0" },"require":{"x/x": "1.0"}},
+                { "name": "d/d", "version": "1.0.0", "replace": {"a/a": "1.0.0", "c/c":"1.0.0" }}
+            ]
+        }
+    ],
+    "require": {
+        "a/a": "1.*",
+        "b/b": "1.*"
+    }
+}
+--RUN--
+install
+--EXPECT-EXIT-CODE--
+2
+--EXPECT--
diff --git a/tests/Composer/Test/Fixtures/installer/replace-root-require.test b/tests/Composer/Test/Fixtures/installer/replace-root-require.test
new file mode 100644
index 000000000000..c00ac4fd59a0
--- /dev/null
+++ b/tests/Composer/Test/Fixtures/installer/replace-root-require.test
@@ -0,0 +1,24 @@
+--TEST--
+Ensure a transiently required replacer can replace root requirements
+--COMPOSER--
+{
+    "repositories": [
+        {
+            "type": "package",
+            "package": [
+                { "name": "a/a", "version": "1.0.0" },
+                { "name": "b/b", "version": "1.0.0", "require": {"c/c": "1.*"} },
+                { "name": "c/c", "version": "1.0.0", "replace": {"a/a": "1.0.0" }}
+            ]
+        }
+    ],
+    "require": {
+        "a/a": "1.*",
+        "b/b": "1.*"
+    }
+}
+--RUN--
+install
+--EXPECT--
+Installing c/c (1.0.0)
+Installing b/b (1.0.0)