dream: pure-SX JSON encode + recursive-descent parse + 35 tests

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/dream/tests/json.sx

@@ -0,0 +1,105 @@
+;; lib/dream/tests/json.sx — JSON encode/parse round-trips.
+
+(define dream-js-pass 0)
+(define dream-js-fail 0)
+(define dream-js-fails (list))
+
+(define
+  dream-js-test
+  (fn
+    (name actual expected)
+    (if
+      (= actual expected)
+      (set! dream-js-pass (+ dream-js-pass 1))
+      (begin
+        (set! dream-js-fail (+ dream-js-fail 1))
+        (append! dream-js-fails {:name name :actual actual :expected expected})))))
+
+;; ── encoding scalars ───────────────────────────────────────────────
+(dream-js-test "encode int" (dream-json-encode 42) "42")
+(dream-js-test "encode float" (dream-json-encode 1.5) "1.5")
+(dream-js-test "encode true" (dream-json-encode true) "true")
+(dream-js-test "encode false" (dream-json-encode false) "false")
+(dream-js-test "encode nil" (dream-json-encode nil) "null")
+(dream-js-test "encode string" (dream-json-encode "hi") "\"hi\"")
+(dream-js-test
+  "encode string escapes quote"
+  (dream-json-encode "a\"b")
+  "\"a\\\"b\"")
+(dream-js-test
+  "encode list"
+  (dream-json-encode (list 1 2 3))
+  "[1,2,3]")
+(dream-js-test
+  "encode list of strings"
+  (dream-json-encode (list "a" "b"))
+  "[\"a\",\"b\"]")
+(dream-js-test
+  "encode single-key dict"
+  (dream-json-encode {:a 1})
+  "{\"a\":1}")
+(dream-js-test "encode empty list" (dream-json-encode (list)) "[]")
+(dream-js-test "encode empty dict" (dream-json-encode {}) "{}")
+
+;; ── parsing scalars ────────────────────────────────────────────────
+(dream-js-test "parse int" (dream-json-parse "5") 5)
+(dream-js-test "parse negative" (dream-json-parse "-7") -7)
+(dream-js-test "parse float" (dream-json-parse "1.5") 1.5)
+(dream-js-test "parse true" (dream-json-parse "true") true)
+(dream-js-test "parse false" (dream-json-parse "false") false)
+(dream-js-test "parse null" (dream-json-parse "null") nil)
+(dream-js-test "parse string" (dream-json-parse "\"hello\"") "hello")
+(dream-js-test "parse string escape" (dream-json-parse "\"a\\nb\"") "a\nb")
+(dream-js-test
+  "parse array"
+  (dream-json-parse "[1,2,3]")
+  (list 1 2 3))
+(dream-js-test "parse empty array" (dream-json-parse "[]") (list))
+(dream-js-test
+  "parse with whitespace"
+  (dream-json-parse "  [ 1 , 2 ]  ")
+  (list 1 2))
+
+;; ── parsing objects ────────────────────────────────────────────────
+(define dream-js-obj (dream-json-parse "{\"x\":5,\"y\":\"hi\"}"))
+(dream-js-test "parse obj number" (get dream-js-obj "x") 5)
+(dream-js-test "parse obj string" (get dream-js-obj "y") "hi")
+(dream-js-test "parse empty obj" (dream-json-parse "{}") {})
+
+;; ── nested ─────────────────────────────────────────────────────────
+(define dream-js-nested (dream-json-parse "{\"a\":[1,{\"b\":2}],\"c\":true}"))
+(dream-js-test
+  "nested array first"
+  (first (get dream-js-nested "a"))
+  1)
+(dream-js-test
+  "nested object in array"
+  (get (nth (get dream-js-nested "a") 1) "b")
+  2)
+(dream-js-test "nested bool" (get dream-js-nested "c") true)
+
+;; ── round-trips ────────────────────────────────────────────────────
+(define dream-js-v {:name "Ada" :age 36 :tags (list "math" "engine")})
+(define dream-js-rt (dream-json-parse (dream-json-encode dream-js-v)))
+(dream-js-test "roundtrip name" (get dream-js-rt "name") "Ada")
+(dream-js-test "roundtrip age" (get dream-js-rt "age") 36)
+(dream-js-test
+  "roundtrip tags"
+  (get dream-js-rt "tags")
+  (list "math" "engine"))
+
+;; ── response + request helpers ─────────────────────────────────────
+(dream-js-test
+  "json-value content-type"
+  (dream-resp-header (dream-json-value {:ok true}) "content-type")
+  "application/json")
+(dream-js-test
+  "json-value body"
+  (dream-resp-body (dream-json-value {:ok true}))
+  "{\"ok\":true}")
+(dream-js-test
+  "json-body parses request"
+  (get (dream-json-body (dream-request "POST" "/" {} "{\"n\":9}")) "n")
+  9)
+
+(define dream-js-tests-run! (fn () {:total (+ dream-js-pass dream-js-fail) :passed dream-js-pass :failed dream-js-fail :fails dream-js-fails}))