fix diffing for strings

Author: bartveneman

diff.js

@@ -37,7 +37,7 @@ function diffStat(statA, statB, key) {
 return diffLists(statA, statB, key)
 }
 
-if (typeof statA === 'string') {
+if (typeof statB === 'string') {
 return diffStrings(statA, statB)
 }
 

test/diff.js

@@ -34,3 +34,13 @@ test('It should return the correct structure when new props are added', t => {
 const result = diff(defaultFixture, fixtureWithAddedProp)
 t.deepEqual(['a', 'b', 'c'], Object.keys(result))
 })
+
+test('It should diff strings correctly after they are introduced in css-analyzer v2.0.0', t => {
+t.deepEqual(diff({}, {'selectors.identifiers.max.value': '.my-selector'}), {
+'selectors.identifiers.max.value': {
+changed: true,
+oldValue: null,
+newValue: '.my-selector'
+}
+})
+})