js-on-sx: String.prototype extensions + Object/Array builtins

Strings: includes, startsWith, endsWith, trim, trimStart, trimEnd, repeat, padStart, padEnd, toString, valueOf. Object: keys, values, entries, assign, freeze (no-op). Array: isArray, of. All wired into js-global. 17 new unit tests. 357/359 unit (+17), 148/148 slice unchanged.
2026-04-23 20:58:24 +00:00
parent 6c4001a299
commit 275d2ecbae
3 changed files with 222 additions and 1 deletions
--- a/lib/js/runtime.sx
+++ b/lib/js/runtime.sx
@@ -885,6 +885,36 @@
      ((>= i (len arr)) acc)
      (else (js-list-reduce-loop f (f acc (nth arr i)) arr (+ i 1))))))

+(define
+  js-string-repeat
+  (fn
+    (s n acc)
+    (if (<= n 0) acc (js-string-repeat s (- n 1) (str acc s)))))
+
+(define
+  js-string-pad
+  (fn
+    (s target pad at-start)
+    (let
+      ((slen (len s)))
+      (if
+        (or (<= target slen) (= (len pad) 0))
+        s
+        (let
+          ((needed (- target slen)))
+          (let
+            ((padding (js-string-pad-build pad needed "")))
+            (if at-start (str padding s) (str s padding))))))))
+
+(define
+  js-string-pad-build
+  (fn
+    (pad needed acc)
+    (cond
+      ((<= needed 0) acc)
+      ((>= (len acc) needed) (js-string-slice acc 0 needed))
+      (else (js-string-pad-build pad needed (str acc pad))))))
+
 (define
  js-string-method
  (fn
@@ -933,6 +963,51 @@
      ((= name "split") (fn (sep) (js-string-split s (js-to-string sep))))
      ((= name "concat")
        (fn (&rest args) (js-string-concat-loop s args 0)))
+      ((= name "includes")
+        (fn
+          (&rest args)
+          (let
+            ((needle (if (= (len args) 0) "" (js-to-string (nth args 0)))))
+            (>= (js-string-index-of s needle 0) 0))))
+      ((= name "startsWith")
+        (fn
+          (&rest args)
+          (let
+            ((needle (if (= (len args) 0) "" (js-to-string (nth args 0))))
+              (start (if (< (len args) 2) 0 (js-num-to-int (nth args 1)))))
+            (js-string-matches? s needle start 0))))
+      ((= name "endsWith")
+        (fn
+          (&rest args)
+          (let
+            ((needle (if (= (len args) 0) "" (js-to-string (nth args 0)))))
+            (let
+              ((end-len (len s)) (n-len (len needle)))
+              (if
+                (> n-len end-len)
+                false
+                (js-string-matches? s needle (- end-len n-len) 0))))))
+      ((= name "trim") (fn () (js-trim s)))
+      ((= name "trimStart") (fn () (js-trim-left s)))
+      ((= name "trimEnd") (fn () (js-trim-right s)))
+      ((= name "repeat")
+        (fn (n) (js-string-repeat s (js-num-to-int n) "")))
+      ((= name "padStart")
+        (fn
+          (&rest args)
+          (let
+            ((target (if (= (len args) 0) 0 (js-num-to-int (nth args 0))))
+              (pad (if (< (len args) 2) " " (js-to-string (nth args 1)))))
+            (js-string-pad s target pad true))))
+      ((= name "padEnd")
+        (fn
+          (&rest args)
+          (let
+            ((target (if (= (len args) 0) 0 (js-num-to-int (nth args 0))))
+              (pad (if (< (len args) 2) " " (js-to-string (nth args 1)))))
+            (js-string-pad s target pad false))))
+      ((= name "toString") (fn () s))
+      ((= name "valueOf") (fn () s))
      (else js-undefined))))

 (define
@@ -1061,6 +1136,17 @@
            ((= key "toLowerCase") (js-string-method obj "toLowerCase"))
            ((= key "split") (js-string-method obj "split"))
            ((= key "concat") (js-string-method obj "concat"))
+            ((= key "includes") (js-string-method obj "includes"))
+            ((= key "startsWith") (js-string-method obj "startsWith"))
+            ((= key "endsWith") (js-string-method obj "endsWith"))
+            ((= key "trim") (js-string-method obj "trim"))
+            ((= key "trimStart") (js-string-method obj "trimStart"))
+            ((= key "trimEnd") (js-string-method obj "trimEnd"))
+            ((= key "repeat") (js-string-method obj "repeat"))
+            ((= key "padStart") (js-string-method obj "padStart"))
+            ((= key "padEnd") (js-string-method obj "padEnd"))
+            ((= key "toString") (js-string-method obj "toString"))
+            ((= key "valueOf") (js-string-method obj "valueOf"))
            (else js-undefined)))
        ((= (type-of obj) "dict")
          (js-dict-get-walk obj (js-to-string key)))
@@ -1347,6 +1433,80 @@
          (dict-set! p "value" reason)
          (js-promise-flush-callbacks! p))))))

+(define
+  js-object-keys
+  (fn
+    (o)
+    (cond
+      ((dict? o)
+        (let
+          ((result (list)))
+          (for-each (fn (k) (append! result k)) (keys o))
+          result))
+      (else (list)))))
+
+(define
+  js-object-values
+  (fn
+    (o)
+    (cond
+      ((dict? o)
+        (let
+          ((result (list)))
+          (for-each (fn (k) (append! result (get o k))) (keys o))
+          result))
+      (else (list)))))
+
+(define
+  js-object-entries
+  (fn
+    (o)
+    (cond
+      ((dict? o)
+        (let
+          ((result (list)))
+          (for-each
+            (fn
+              (k)
+              (let
+                ((pair (list)))
+                (append! pair k)
+                (append! pair (get o k))
+                (append! result pair)))
+            (keys o))
+          result))
+      (else (list)))))
+
+(define
+  js-object-assign
+  (fn
+    (&rest args)
+    (cond
+      ((= (len args) 0) (dict))
+      (else
+        (let
+          ((target (nth args 0)))
+          (for-each
+            (fn
+              (src)
+              (when
+                (dict? src)
+                (for-each
+                  (fn (k) (dict-set! target k (get src k)))
+                  (keys src))))
+            (rest args))
+          target)))))
+
+(define js-object-freeze (fn (o) o))
+
+(define Object {:entries js-object-entries :values js-object-values :freeze js-object-freeze :assign js-object-assign :keys js-object-keys})
+
+(define js-array-is-array (fn (v) (list? v)))
+
+(define js-array-of (fn (&rest args) args))
+
+(define Array {:isArray js-array-is-array :of js-array-of})
+
 (define
  js-promise-flush-callbacks!
  (fn
@@ -1761,4 +1921,4 @@
        (str "/" (get rx "source") "/" (get rx "flags")))
      (else js-undefined))))

-(define js-global {:isFinite js-global-is-finite :console console :Number Number :Math Math :NaN 0 :Infinity inf :isNaN js-global-is-nan :undefined js-undefined})
+(define js-global {:isFinite js-global-is-finite :console console :Number Number :Math Math :Array Array :NaN 0 :Infinity inf :isNaN js-global-is-nan :Object Object :undefined js-undefined})
--- a/lib/js/test.sh
+++ b/lib/js/test.sh
@@ -899,6 +899,44 @@ cat > "$TMPFILE" << 'EPOCHS'
 (epoch 1310)
 (eval "(js-eval \"var sum = 0; for (var i = 1; i <= 5; i++) sum = sum + i; sum\")")

+;; ── Phase 11.strings: extended String.prototype methods ─────────
+(epoch 1400)
+(eval "(js-eval \"'hello world'.includes('world')\")")
+(epoch 1401)
+(eval "(js-eval \"'hello world'.includes('xyz')\")")
+(epoch 1402)
+(eval "(js-eval \"'hello'.startsWith('hel')\")")
+(epoch 1403)
+(eval "(js-eval \"'hello'.startsWith('llo')\")")
+(epoch 1404)
+(eval "(js-eval \"'hello'.endsWith('llo')\")")
+(epoch 1405)
+(eval "(js-eval \"'hello'.endsWith('hel')\")")
+(epoch 1406)
+(eval "(js-eval \"'  hi  '.trim()\")")
+(epoch 1407)
+(eval "(js-eval \"'abc'.repeat(3)\")")
+(epoch 1408)
+(eval "(js-eval \"'5'.padStart(3, '0')\")")
+(epoch 1409)
+(eval "(js-eval \"'5'.padEnd(3, 'x')\")")
+(epoch 1410)
+(eval "(js-eval \"'hello'.toString()\")")
+
+;; ── Phase 11.object: Object builtin ─────────────────────────────
+(epoch 1500)
+(eval "(js-eval \"Object.keys({a:1, b:2}).length\")")
+(epoch 1501)
+(eval "(js-eval \"Object.values({a:1, b:2}).length\")")
+(epoch 1502)
+(eval "(js-eval \"var o = Object.assign({a:1}, {b:2}); o.a + o.b\")")
+(epoch 1503)
+(eval "(js-eval \"Array.isArray([1,2])\")")
+(epoch 1504)
+(eval "(js-eval \"Array.isArray('abc')\")")
+(epoch 1505)
+(eval "(js-eval \"Array.of(1,2,3).length\")")
+
 EPOCHS

 OUTPUT=$(timeout 180 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
@@ -1377,6 +1415,27 @@ check 1308 "a[1]++"                         '3'
 check 1309 "for-loop x++"                   '8'
 check 1310 "for-loop accumulator"           '15'

+# ── Phase 11.strings: extended String.prototype ─────────────────
+check 1400 "includes match"                 'true'
+check 1401 "includes no match"              'false'
+check 1402 "startsWith match"               'true'
+check 1403 "startsWith no match"            'false'
+check 1404 "endsWith match"                 'true'
+check 1405 "endsWith no match"              'false'
+check 1406 "trim whitespace"                '"hi"'
+check 1407 "repeat 3x"                      '"abcabcabc"'
+check 1408 "padStart 0s"                    '"005"'
+check 1409 "padEnd x"                       '"5xx"'
+check 1410 "toString self"                  '"hello"'
+
+# ── Phase 11.object: Object + Array ─────────────────────────────
+check 1500 "Object.keys count"              '2'
+check 1501 "Object.values.length"           '2'
+check 1502 "Object.assign merge"            '3'
+check 1503 "Array.isArray yes"              'true'
+check 1504 "Array.isArray no"               'false'
+check 1505 "Array.of length"                '3'
+
 TOTAL=$((PASS + FAIL))
 if [ $FAIL -eq 0 ]; then
  echo "✓ $PASS/$TOTAL JS-on-SX tests passed"
--- a/plans/js-on-sx.md
+++ b/plans/js-on-sx.md
@@ -179,6 +179,8 @@ Append-only record of completed iterations. Loop writes one line per iteration:

 - 2026-04-23 — **Postfix/prefix `++` / `--`.** Parser: postfix branch in `jp-parse-postfix` (matches `op ++`/`--` after the current expression and emits `(js-postfix op target)`), prefix branch in `jp-parse-primary` *before* the unary-`-/+/!/~` path emits `(js-prefix op target)`. Transpile: `js-transpile-prefix` emits `(set! sxname (+ (js-to-number sxname) ±1))` for idents, `(js-set-prop obj key (+ (js-to-number (js-get-prop obj key)) ±1))` for members/indices. `js-transpile-postfix` uses a `let` binding to cache the old value via `js-to-number`, then updates and returns the saved value — covers ident, member, and index targets. 11 new unit tests (ident inc/dec, pre vs post return value, obj.key, a[i], in `for(;; i++)`, accumulator loop), **340/342** (329→+11). Conformance unchanged.

+- 2026-04-23 — **String.prototype extensions + Object/Array builtins.** Strings: added `includes`, `startsWith`, `endsWith`, `trim`, `trimStart`, `trimEnd`, `repeat`, `padStart`, `padEnd`, `toString`, `valueOf` to `js-string-method` dispatch and corresponding `js-get-prop` string-branch keys. Helpers: `js-string-repeat` (tail-recursive concat), `js-string-pad` + `js-string-pad-build`. Object: `Object.keys / .values / .entries / .assign / .freeze` (freeze is a no-op — we don't track sealed state). Array: `Array.isArray` (backed by `list?`), `Array.of` (varargs → list). Wired into `js-global`. 17 new unit tests, **357/359** (340→+17). Conformance unchanged. Gotcha: SX's `keys` primitive returns most-recently-inserted-first, so `Object.keys({a:1, b:2})` comes back `["b", "a"]`. Test assertion has to check `.length` rather than the literal pair. If spec order matters for a real app, Object.keys would need its own ordered traversal.
+
 ## Phase 3-5 gotchas

 Worth remembering for later phases: