1 files changed, 64 insertions, 0 deletions
diff --git a/unit-tests/directive-export-gmake.mk b/unit-tests/directive-export-gmake.mk
new file mode 100644
index 0000000000000..51de8fe55f64e
--- /dev/null
+++ b/unit-tests/directive-export-gmake.mk
@@ -0,0 +1,64 @@
+# $NetBSD: directive-export-gmake.mk,v 1.2 2020/10/19 18:59:53 rillig Exp $
+#
+# Tests for the export directive (without leading dot), as in GNU make.
+
+# The "export" directive only affects the environment of the make process
+# and its child processes.  It does not affect the global variables or any
+# other variables.
+VAR=	before
+export VAR=exported
+.if ${VAR} != "before"
+.  error
+.endif
+
+# Ensure that the name-value pair is actually exported.
+.if ${:!echo "\$VAR"!} != "exported"
+.  error
+.endif
+
+# This line looks like it would export 2 variables, but it doesn't.
+# It only exports VAR and appends everything else as the variable value.
+export VAR=exported VAR2=exported-as-well
+.if ${:!echo "\$VAR"!} != "exported VAR2=exported-as-well"
+.  error ${:!echo "\$VAR"!}
+.endif
+
+# Contrary to the usual variable assignments, spaces are significant
+# after the '=' sign and are prepended to the value of the environment
+# variable.
+export VAR=  leading spaces
+.if ${:!echo "\$VAR"!} != "  leading spaces"
+.  error
+.endif
+
+# Contrary to the usual variable assignments, spaces are significant
+# before the '=' sign and are appended to the name of the environment
+# variable.
+#
+# Depending on the shell, environment variables with such exotic names
+# may be silently discarded.  One such shell is dash, which is the default
+# shell on Ubuntu and Debian.
+export VAR =trailing space in varname
+.if ${:!env | grep trailing!} != "VAR =trailing space in varname"
+.  if ${:!env | grep trailing!} != "" # for dash
+.    error
+.  endif
+.endif
+
+# The right-hand side of the exported variable is expanded exactly once.
+TWICE=	expanded twice
+ONCE=	expanded once, leaving $${TWICE} as-is
+export VAR=${ONCE}
+.if ${:!echo "\$VAR"!} != "expanded once, leaving \${TWICE} as-is"
+.  error
+.endif
+
+# Undefined variables are allowed on the right-hand side, they expand
+# to an empty string, as usual.
+export VAR=an ${UNDEF} variable
+.if ${:!echo "\$VAR"!} != "an  variable"
+.  error
+.endif
+
+all:
+	@:;