Add refactoring rule to suggest hash instead of make-immutable-hash with quasiquote

Co-authored-by: jackfirth <[email protected]>

Author: Copilot

default-recommendations/hash-shortcuts-test.rkt

@@ -295,3 +295,63 @@ no-change-test:
   (define sum (hash-ref! h1 (cadr term) 0))
   (hash-set! h2 (cadr term) (+ (car term) sum)))
 ------------------------------
+
+
+test: "make-immutable-hash with quasiquoted pairs can be simplified to hash"
+------------------------------
+(define body 'test-body)
+(define event 'test-event)
+(define comments '(c1 c2))
+(make-immutable-hash
+ `((body . ,body)
+   (event . ,event)
+   (comments . ,(map values comments))))
+==============================
+(define body 'test-body)
+(define event 'test-event)
+(define comments '(c1 c2))
+(hash 'body body 'event event 'comments (map values comments))
+------------------------------
+
+
+test: "make-immutable-hash with simple quasiquoted pairs can be simplified to hash"
+------------------------------
+(define x 1)
+(define y 2)
+(make-immutable-hash `((a . ,x) (b . ,y)))
+==============================
+(define x 1)
+(define y 2)
+(hash 'a x 'b y)
+------------------------------
+
+
+test: "make-immutable-hash with single pair can be simplified to hash"
+------------------------------
+(define value 42)
+(make-immutable-hash `((key . ,value)))
+==============================
+(define value 42)
+(hash 'key value)
+------------------------------
+
+
+no-change-test: "make-immutable-hash without quasiquote should not be changed"
+------------------------------
+(make-immutable-hash '((a . 1) (b . 2)))
+------------------------------
+
+
+no-change-test: "make-immutable-hash with variable keys should not be changed"
+------------------------------
+(define k 'key)
+(define v 'value)
+(make-immutable-hash `((,k . ,v)))
+------------------------------
+
+
+no-change-test: "make-immutable-hash with list literal should not be changed"
+------------------------------
+(define pairs '((a . 1) (b . 2)))
+(make-immutable-hash pairs)
+------------------------------

default-recommendations/hash-shortcuts.rkt

@@ -159,6 +159,25 @@
   (hash-values h))
 
 
+(define-syntax-class quoted-key
+  #:attributes (key)
+  #:literals (quote)
+  (pattern (quote key:id)))
+
+
+(define-syntax-class hash-pair-with-quoted-key
+  #:attributes (key value)
+  #:literals (unquote)
+  (pattern (key:id unquote value)))
+
+
+(define-refactoring-rule make-immutable-hash-with-quasiquote-to-hash
+  #:description "This `make-immutable-hash` with quasiquoted pairs can be replaced with a simpler `hash` call."
+  #:literals (make-immutable-hash quasiquote)
+  (make-immutable-hash (quasiquote (pair:hash-pair-with-quoted-key ...)))
+  (hash (~@ 'pair.key pair.value) ...))
+
+
 (define-refactoring-suite hash-shortcuts
   #:rules (define-hash-ref-set!-to-hash-update!
             hash-map-to-hash-keys
@@ -169,4 +188,5 @@
            hash-ref-with-constant-lambda-to-hash-ref-without-lambda
            hash-ref!-with-constant-lambda-to-hash-ref!-without-lambda
            hash-set!-ref-to-hash-update!
+           make-immutable-hash-with-quasiquote-to-hash
            or-hash-ref-set!-to-hash-ref!))