test-coercion-matrix.js
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	// ============================================
	// TEST: String coercion comparison matrix
	// ============================================
	// Compares: concat, template, String(), toString()
	// ============================================

	console.log("=== STRING COERCION MATRIX ===\n");

	function safe(fn) {
	try {
	const result = fn();
	if (result === undefined) return "undefined";
	if (result === null) return "null";
	return result;
	} catch (e) {
	return "ERROR:" + e.name;
	}
	}

	function test(name, value) {
	console.log(name + ":");
	console.log(" concat: " + safe(function() { return "" + value; }));
	console.log(" template: " + safe(function() { return `${value}`; }));
	console.log(" String(): " + safe(function() { return String(value); }));
	if (value !== null && value !== undefined) {
	console.log(" toString: " + safe(function() { return value.toString(); }));
	}
	console.log("");
	}

	// Primitives
	console.log("--- PRIMITIVES ---\n");
	test("number 42", 42);
	test("number 0", 0);
	test("number -1", -1);
	test("number NaN", NaN);
	test("number Infinity", Infinity);
	test("string 'hello'", "hello");
	test("string ''", "");
	test("boolean true", true);
	test("boolean false", false);
	test("null", null);
	test("undefined", undefined);
	test("BigInt 123n", 123n);

	// Symbol
	console.log("--- SYMBOL ---\n");
	test("Symbol('test')", Symbol("test"));

	// Arrays
	console.log("--- ARRAYS ---\n");
	test("[]", []);
	test("[1, 2, 3]", [1, 2, 3]);
	test("[[1,2], [3,4]]", [[1, 2], [3, 4]]);
	test("[null, undefined]", [null, undefined]);
	test("['a', 'b']", ["a", "b"]);

	// Functions
	console.log("--- FUNCTIONS ---\n");
	test("() => 1", () => 1);
	test("function() {}", function() {});
	function namedFn() { return 1; }
	test("named function", namedFn);
	test("async () => 1", async () => 1);

	// Objects
	console.log("--- OBJECTS ---\n");
	test("{}", {});
	test("{ a: 1 }", { a: 1 });
	test("{ a: 1, b: 2 }", { a: 1, b: 2 });

	// Built-in objects
	console.log("--- BUILT-IN OBJECTS ---\n");
	test("new Date(0)", new Date(0));
	test("new Date()", new Date());
	test("/test/gi", /test/gi);
	test("new Error('oops')", new Error("oops"));
	test("new TypeError('bad')", new TypeError("bad"));
	test("new Map([['a',1]])", new Map([["a", 1]]));
	test("new Set([1,2,3])", new Set([1, 2, 3]));
	test("new WeakMap()", new WeakMap());
	test("new WeakSet()", new WeakSet());
	test("new ArrayBuffer(8)", new ArrayBuffer(8));
	test("new Uint8Array([1,2])", new Uint8Array([1, 2]));
	test("Promise.resolve(1)", Promise.resolve(1));

	// Custom toString
	console.log("--- CUSTOM toString (CRASH TESTS) ---\n");

	console.log("native toString (should work):");
	test("{ toString: Object.prototype.toString }", { toString: Object.prototype.toString });

	console.log("user toString (may crash):");
	const userToString = { toString: function() { return "custom"; } };
	console.log(" direct call works: " + userToString.toString());
	test("{ toString: fn => 'custom' }", userToString);

	console.log("arrow toString (may crash):");
	const arrowToString = { toString: () => "arrow" };
	console.log(" direct call works: " + arrowToString.toString());
	test("{ toString: () => 'arrow' }", arrowToString);

	// Custom valueOf
	console.log("--- CUSTOM valueOf ---\n");
	test("{ valueOf: fn => 42 }", { valueOf: function() { return 42; } });
	test("{ valueOf: fn => 'val' }", { valueOf: function() { return "val"; } });

	// Symbol.toPrimitive
	console.log("--- Symbol.toPrimitive ---\n");
	const withPrimitive = {};
	withPrimitive[Symbol.toPrimitive] = function(hint) { return "hint:" + hint; };
	test("{ [Symbol.toPrimitive]: fn }", withPrimitive);

	// Class instances
	console.log("--- CLASS INSTANCES ---\n");

	class WithToString {
	toString() { return "class-toString"; }
	}
	console.log("class with toString method:");
	const inst1 = new WithToString();
	console.log(" direct call works: " + inst1.toString());
	test("new WithToString()", inst1);

	class WithValueOf {
	valueOf() { return "class-valueOf"; }
	}
	test("new WithValueOf()", new WithValueOf());

	class PlainClass {}
	test("new PlainClass()", new PlainClass());

	console.log("=== SUMMARY ===\n");
	console.log("Check for:");
	console.log("1. Missing output after test name = SILENT CRASH");
	console.log("2. '[Function: ...]' instead of function source = INSPECT BUG");
	console.log("3. '{ ... }' or '[ ... ]' with spaces = INSPECT BUG");
	console.log("4. Different results between concat and template = BUG");
	console.log("");

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