Module Name: src
Committed By: rillig
Date: Fri Aug 28 13:50:48 UTC 2020
Modified Files:
src/usr.bin/make/unit-tests: cond-op.mk
Log Message:
make(1): add test for operator precedence in conditions
To generate a diff of this commit:
cvs rdiff -u -r1.2 -r1.3 src/usr.bin/make/unit-tests/cond-op.mk
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/unit-tests/cond-op.mk
diff -u src/usr.bin/make/unit-tests/cond-op.mk:1.2 src/usr.bin/make/unit-tests/cond-op.mk:1.3
--- src/usr.bin/make/unit-tests/cond-op.mk:1.2 Sun Aug 16 14:25:16 2020
+++ src/usr.bin/make/unit-tests/cond-op.mk Fri Aug 28 13:50:48 2020
@@ -1,8 +1,42 @@
-# $NetBSD: cond-op.mk,v 1.2 2020/08/16 14:25:16 rillig Exp $
+# $NetBSD: cond-op.mk,v 1.3 2020/08/28 13:50:48 rillig Exp $
#
# Tests for operators like &&, ||, ! in .if conditions.
+#
+# See also:
+# cond-op-and.mk
+# cond-op-not.mk
+# cond-op-or.mk
+# cond-op-parentheses.mk
+
+# In make, && binds more tightly than ||, like in C.
+# If make had the same precedence for both && and ||, the result would be
+# different.
+# If || were to bind more tightly than &&, the result would be different
+# as well.
+.if !(1 || 1 && 0)
+.error
+.endif
+
+# If make were to interpret the && and || operators like the shell, the
+# implicit binding would be this:
+.if (1 || 1) && 0
+.error
+.endif
+
+# The precedence of the ! operator is different from C though. It has a
+# lower precedence than the comparison operators.
+.if !"word" == "word"
+.error
+.endif
+
+# This is how the above condition is actually interpreted.
+.if !("word" == "word")
+.error
+.endif
-# TODO: Implementation
+# TODO: Demonstrate that the precedence of the ! and == operators actually
+# makes a difference. There is a simple example for sure, I just cannot
+# wrap my head around it.
all:
@:;
