New Feature: stringify (#46)

* Implement stringify, the reverse transform of parse

* Properly JSON encode the attrValues when calling stringify, added tests

* Remove unused file to fix watch

* Ensure that logical operators are stringified correctly if they have more than 2 filters

* Remove nested template literal

* Add stringify to readme / minor cleanup

* GH markdown requires space after the sharps

Co-authored-by: Thomas Poignant <[email protected]>

Author: patrickmcdougle-okta

README.md

@@ -12,9 +12,8 @@ This is a fork https://www.npmjs.com/package/scim2-filter version 0.2.0 with bug
 
 usage
 -----
-
+### parse
 You can parse filter query and get ast.
-
 ```javascript
 import {parse} from 'scim2-parse-filter';
 
@@ -50,7 +49,7 @@ assert.deepEqual(f, {
 });
 ```
 
-
+### filter
 and You can use filter in json.
 
 ```javascript
@@ -65,5 +64,41 @@ const ret = users.filter(f);
 assert.deepEqual(ret, [users[0]]);
 ```
 
+### stringify
+and you can convert an AST back into a SCIM query.
+
+```typescript
+import { Filter, stringify } from 'scim2-parse-filter';
 
+const ast: Filter = {
+  op:"and",
+  filters:[
+    {
+      op:"eq",
+      attrPath:"userType",
+      compValue:"Employee"
+    },
+    {
+      op:"[]",
+      attrPath:"emails",
+      valFilter:{
+        op:"and",
+        filters:[
+          {
+            op:"eq",
+            attrPath:"type",
+            compValue:"work"
+          },
+          {
+            op:"co",
+            attrPath:"value",
+            compValue:"@example.com"
+          }
+        ]
+      }
+    }
+  ]
+};
 
+assert.deepEqual(stringify(ast), 'userType eq "Employee" and emails[type eq "work" and value co "@example.com"]');
+```