Add missing common.asm test harness file

tools/tests/unit/common.asm

@@ -0,0 +1,62 @@
+; *** requirements ***
+; ascii.h
+; core
+; stdio
+; lib/ari
+; lib/fmt
+
+testNum:	.db 1
+
+STDIO_PUTC:
+	out	(0), a
+	cp	a
+	ret
+
+STDIO_GETC:
+	jp	unsetZ
+
+assertZ:
+	ret	z
+	ld	hl, .msg
+	call	printstr
+	jp	fail
+.msg:
+	.db	"Z not set", CR, LF, 0
+
+assertNZ:
+	ret	nz
+	ld	hl, .msg
+	call	printstr
+	jp	fail
+.msg:
+	.db	"Z set", CR, LF, 0
+
+; Assert that HL == DE
+assertEQW:
+	ld	a, h
+	cp	d
+	jr	nz, .fail
+	ld	a, l
+	cp	e
+	ret	z
+.fail:
+	call	printHexPair
+	call	printcrlf
+	ex	de, hl
+	call	printHexPair
+	call	printcrlf
+	ld	hl, .msg
+	call	printstr
+	jp	fail
+.msg:
+	.db	"HL != DE", CR, LF, 0
+
+nexttest:
+	ld	a, (testNum)
+	inc	a
+	ld	(testNum), a
+	ret
+
+fail:
+	ld	a, (testNum)
+	halt