Add test to demonstrate lack of expansions in skipIfBlock (#1516)

test/asm/skip-expansions.asm

@@ -0,0 +1,31 @@
+; skipping ahead to `elif`/`else`/`endc`/`endr`/`endm` disables expansions!
+
+MACRO mac1
+	if _NARG != 2
+		println "args: \#"
+	elif (\2) == 42  
+		println "forty-two!"
+	else
+		println "it's ", (\2)
+	endc
+ENDM
+
+	mac1 elif, 6 * 7  ; this prints "forty-two!" because it takes the `elif`
+	mac1 elif, 6 * 9
+	mac1 elif
+	mac1
+
+MACRO mac2
+	if _NARG != 2
+		println "args: \#"
+	\1 (\2) == 42  ; if the `if` is not taken, this is not expanded!
+		println "forty-two!"
+	else
+		println "it's ", (\2)
+	endc
+ENDM
+
+	mac2 elif, 6 * 7  ; this prints "it's $2A" because it skips the `\1` line and takes the `else`
+	mac2 elif, 6 * 9
+	mac2 elif
+	mac2

test/asm/skip-expansions.err

@@ -0,0 +1,5 @@
+error: skip-expansions.asm(31) -> skip-expansions.asm::mac2(21):
+    Macro argument '\1' not defined
+error: skip-expansions.asm(31) -> skip-expansions.asm::mac2(21):
+    syntax error, unexpected (
+error: Assembly aborted (2 errors)!

test/asm/skip-expansions.out

@@ -0,0 +1,8 @@
+forty-two!
+it's $36
+args: elif
+args: 
+it's $2A
+it's $36
+args: elif
+args: