feat: add support for toml in addition to json

test_data/full.json

@@ -0,0 +1,5 @@
+{
+  "String": "default string",
+  "Invariant": "should not change",
+  "Int": 1
+}

test_data/full.toml

@@ -0,0 +1,3 @@
+String = 'default string'
+Invariant = 'should not change'
+Int = 1

test_data/invalid.toml

@@ -0,0 +1 @@
+String: not toml

test_data/part1.json

@@ -0,0 +1 @@
+{"String": "foo"}

test_data/part1.toml

@@ -0,0 +1 @@
+String = "foo"

test_data/part2.json

@@ -0,0 +1 @@
+{"Int": 42}

test_data/part2.toml

@@ -0,0 +1 @@
+Int = 42

test_data/same1.json

@@ -0,0 +1 @@
+{"String": "foo"}

test_data/same1.toml

@@ -0,0 +1 @@
+String = "foo"

test_data/same2.json

@@ -0,0 +1 @@
+{"String": "bar"}

test_data/same2.toml

@@ -0,0 +1 @@
+String = "bar"

test_data/unknown.json

@@ -0,0 +1,5 @@
+{
+    "String": "config string",
+    "Int": 42,
+    "Unknown": "foo"
+}

test_data/unknown.toml

@@ -0,0 +1,3 @@
+String = "config string"
+Int = 42
+Unknown = "foo"

test_data/valid.toml

@@ -0,0 +1,2 @@
+string = "config string"
+int = 42

test_data/valid.unknown

@@ -0,0 +1 @@
+String: not json