;; String>>format: and printOn: tests.

(set! st-test-pass 0)
(set! st-test-fail 0)
(set! st-test-fails (list))

(st-bootstrap-classes!)
(define ev (fn (src) (smalltalk-eval src)))
(define evp (fn (src) (smalltalk-eval-program src)))

;; ── 1. String>>format: ──
(st-test "format: single placeholder"
  (ev "'Hello, {1}!' format: #('World')")
  "Hello, World!")

(st-test "format: multiple placeholders"
  (ev "'{1} + {2} = {3}' format: #(1 2 3)")
  "1 + 2 = 3")

(st-test "format: out-of-order"
  (ev "'{2} {1}' format: #('first' 'second')")
  "second first")

(st-test "format: repeated index"
  (ev "'{1}-{1}-{1}' format: #(#a)")
  "a-a-a")

(st-test "format: empty source"
  (ev "'' format: #()") "")

(st-test "format: no placeholders"
  (ev "'plain text' format: #()") "plain text")

(st-test "format: unmatched {"
  (ev "'open { brace' format: #('x')")
  "open { brace")

(st-test "format: out-of-range index keeps literal"
  (ev "'{99}' format: #('hi')")
  "{99}")

(st-test "format: numeric arg"
  (ev "'value: {1}' format: #(42)")
  "value: 42")

(st-test "format: float arg"
  (ev "'pi ~ {1}' format: #(3.14)")
  "pi ~ 3.14")

;; ── 2. printOn: writes printString to stream ──
(st-test "printOn: writes int via stream"
  (evp
    "| s |
     s := WriteStream on: (Array new: 0).
     42 printOn: s.
     ^ s contents")
  (list "4" "2"))

(st-test "printOn: writes string"
  (evp
    "| s |
     s := WriteStream on: (Array new: 0).
     'hi' printOn: s.
     ^ s contents")
  (list "'" "h" "i" "'"))

(st-test "printOn: returns receiver"
  (evp
    "| s |
     s := WriteStream on: (Array new: 0).
     ^ 99 printOn: s")
  99)

;; ── 3. Universal printString fallback for user instances ──
(st-class-define! "Cat" "Object" (list))
(st-class-define! "Animal" "Object" (list))

(st-test "printString of vowel-initial class"
  (evp "^ Animal new printString")
  "an Animal")

(st-test "printString of consonant-initial class"
  (evp "^ Cat new printString")
  "a Cat")

(st-test "user override of printString wins"
  (begin
    (st-class-add-method! "Cat" "printString"
      (st-parse-method "printString ^ #miaow asString"))
    (str (evp "^ Cat new printString")))
  "miaow")

;; ── 4. printOn: on user instance with overridden printString ──
(st-test "printOn: respects user-overridden printString"
  (evp
    "| s |
     s := WriteStream on: (Array new: 0).
     Cat new printOn: s.
     ^ s contents")
  (list "m" "i" "a" "o" "w"))

;; ── 5. printString for class-refs ──
(st-test "Class printString is its name"
  (ev "Animal printString") "Animal")

;; ── 6. format: combined with printString ──
(st-class-define! "Box" "Object" (list "n"))
(st-class-add-method! "Box" "n:"
  (st-parse-method "n: v n := v. ^ self"))
(st-class-add-method! "Box" "printString"
  (st-parse-method "printString ^ '<' , n printString , '>'"))

(st-test "format: with custom printString in arg"
  (str (evp
    "| b | b := Box new n: 7.
     ^ '({1})' format: (Array with: b printString)"))
  "(<7>)")

(st-class-add-class-method! "Array" "with:"
  (st-parse-method "with: x | a | a := Array new: 1. a at: 1 put: x. ^ a"))

(list st-test-pass st-test-fail)