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Diffstat (limited to 'contrib/bmake/unit-tests/cond-short.mk')
| -rw-r--r-- | contrib/bmake/unit-tests/cond-short.mk | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/contrib/bmake/unit-tests/cond-short.mk b/contrib/bmake/unit-tests/cond-short.mk new file mode 100644 index 000000000000..46c7ea26a97b --- /dev/null +++ b/contrib/bmake/unit-tests/cond-short.mk @@ -0,0 +1,216 @@ +# $NetBSD: cond-short.mk,v 1.15 2020/12/01 19:37:23 rillig Exp $ +# +# Demonstrates that in conditions, the right-hand side of an && or || +# is only evaluated if it can actually influence the result. +# This is called 'short-circuit evaluation' and is the usual evaluation +# mode in most programming languages. A notable exception is Ada, which +# distinguishes between the operators 'And', 'And Then', 'Or', 'Or Else'. +# +# Before 2020-06-28, the right-hand side of an && or || operator was always +# evaluated, which was wrong. In cond.c 1.69 and var.c 1.197 on 2015-10-11, +# Var_Parse got a new parameter named 'wantit'. Since then it would have been +# possible to skip evaluation of irrelevant variable expressions and only +# parse them. They were still evaluated though, the only difference to +# relevant variable expressions was that in the irrelevant variable +# expressions, undefined variables were allowed. + +# The && operator. + +.if 0 && ${echo "unexpected and" 1>&2 :L:sh} +.endif + +.if 1 && ${echo "expected and" 1>&2 :L:sh} +.endif + +.if 0 && exists(nonexistent${echo "unexpected and exists" 1>&2 :L:sh}) +.endif + +.if 1 && exists(nonexistent${echo "expected and exists" 1>&2 :L:sh}) +.endif + +.if 0 && empty(${echo "unexpected and empty" 1>&2 :L:sh}) +.endif + +.if 1 && empty(${echo "expected and empty" 1>&2 :L:sh}) +.endif + +# "VAR U11" is not evaluated; it was evaluated before 2020-07-02. +# The whole !empty condition is only parsed and then discarded. +VAR= ${VAR${:U11${echo "unexpected VAR U11" 1>&2 :L:sh}}} +VAR13= ${VAR${:U12${echo "unexpected VAR13" 1>&2 :L:sh}}} +.if 0 && !empty(VAR${:U13${echo "unexpected U13 condition" 1>&2 :L:sh}}) +.endif + +VAR= ${VAR${:U21${echo "unexpected VAR U21" 1>&2 :L:sh}}} +VAR23= ${VAR${:U22${echo "expected VAR23" 1>&2 :L:sh}}} +.if 1 && !empty(VAR${:U23${echo "expected U23 condition" 1>&2 :L:sh}}) +.endif +VAR= # empty again, for the following tests + +# The :M modifier is only parsed, not evaluated. +# Before 2020-07-02, it was wrongly evaluated. +.if 0 && !empty(VAR:M${:U${echo "unexpected M pattern" 1>&2 :L:sh}}) +.endif + +.if 1 && !empty(VAR:M${:U${echo "expected M pattern" 1>&2 :L:sh}}) +.endif + +.if 0 && !empty(VAR:S,from,${:U${echo "unexpected S modifier" 1>&2 :L:sh}},) +.endif + +.if 0 && !empty(VAR:C,from,${:U${echo "unexpected C modifier" 1>&2 :L:sh}},) +.endif + +.if 0 && !empty("" == "" :? ${:U${echo "unexpected ? modifier" 1>&2 :L:sh}} :) +.endif + +.if 0 && !empty(VAR:old=${:U${echo "unexpected = modifier" 1>&2 :L:sh}}) +.endif + +.if 0 && !empty(1 2 3:L:@var@${:U${echo "unexpected @ modifier" 1>&2 :L:sh}}@) +.endif + +.if 0 && !empty(:U${:!echo "unexpected exclam modifier" 1>&2 !}) +.endif + +# Irrelevant assignment modifiers are skipped as well. +.if 0 && ${1 2 3:L:@i@${FIRST::?=$i}@} +.endif +.if 0 && ${1 2 3:L:@i@${LAST::=$i}@} +.endif +.if 0 && ${1 2 3:L:@i@${APPENDED::+=$i}@} +.endif +.if 0 && ${echo.1 echo.2 echo.3:L:@i@${RAN::!=${i:C,.*,&; & 1>\&2,:S,., ,g}}@} +.endif +.if defined(FIRST) || defined(LAST) || defined(APPENDED) || defined(RAN) +. warning first=${FIRST} last=${LAST} appended=${APPENDED} ran=${RAN} +.endif + +# The || operator. + +.if 1 || ${echo "unexpected or" 1>&2 :L:sh} +.endif + +.if 0 || ${echo "expected or" 1>&2 :L:sh} +.endif + +.if 1 || exists(nonexistent${echo "unexpected or exists" 1>&2 :L:sh}) +.endif + +.if 0 || exists(nonexistent${echo "expected or exists" 1>&2 :L:sh}) +.endif + +.if 1 || empty(${echo "unexpected or empty" 1>&2 :L:sh}) +.endif + +.if 0 || empty(${echo "expected or empty" 1>&2 :L:sh}) +.endif + +# Unreachable nested conditions are skipped completely as well. + +.if 0 +. if ${echo "unexpected nested and" 1>&2 :L:sh} +. endif +.endif + +.if 1 +.elif ${echo "unexpected nested or" 1>&2 :L:sh} +.endif + +# make sure these do not cause complaint +#.MAKEFLAGS: -dc + +# TODO: Rewrite this whole section and check all the conditions and variables. +# Several of the assumptions are probably wrong here. +# TODO: replace 'x=' with '.info' or '.error'. +V42= 42 +iV1= ${V42} +iV2= ${V66} + +.if defined(V42) && ${V42} > 0 +x= Ok +.else +x= Fail +.endif +x!= echo 'defined(V42) && $${V42} > 0: $x' >&2; echo + +# With cond.c 1.76 from 2020-07-03, the following condition triggered a +# warning: "String comparison operator should be either == or !=". +# This was because the variable expression ${iV2} was defined, but the +# contained variable V66 was undefined. The left-hand side of the comparison +# therefore evaluated to the string "${V66}", which is obviously not a number. +# +# This was fixed in cond.c 1.79 from 2020-07-09 by not evaluating irrelevant +# comparisons. Instead, they are only parsed and then discarded. +# +# At that time, there was not enough debug logging to see the details in the +# -dA log. To actually see it, add debug logging at the beginning and end of +# Var_Parse. +.if defined(V66) && ( ${iV2} < ${V42} ) +x= Fail +.else +x= Ok +.endif +# XXX: This condition doesn't match the one above. The quotes are missing +# above. This is a crucial detail since without quotes, the variable +# expression ${iV2} evaluates to "${V66}", and with quotes, it evaluates to "" +# since undefined variables are allowed and expand to an empty string. +x!= echo 'defined(V66) && ( "$${iV2}" < $${V42} ): $x' >&2; echo + +.if 1 || ${iV1} < ${V42} +x= Ok +.else +x= Fail +.endif +x!= echo '1 || $${iV1} < $${V42}: $x' >&2; echo + +# With cond.c 1.76 from 2020-07-03, the following condition triggered a +# warning: "String comparison operator should be either == or !=". +# This was because the variable expression ${iV2} was defined, but the +# contained variable V66 was undefined. The left-hand side of the comparison +# therefore evaluated to the string "${V66}", which is obviously not a number. +# +# This was fixed in cond.c 1.79 from 2020-07-09 by not evaluating irrelevant +# comparisons. Instead, they are only parsed and then discarded. +# +# At that time, there was not enough debug logging to see the details in the +# -dA log. To actually see it, add debug logging at the beginning and end of +# Var_Parse. +.if 1 || ${iV2:U2} < ${V42} +x= Ok +.else +x= Fail +.endif +x!= echo '1 || $${iV2:U2} < $${V42}: $x' >&2; echo + +# the same expressions are fine when the lhs is expanded +# ${iV1} expands to 42 +.if 0 || ${iV1} <= ${V42} +x= Ok +.else +x= Fail +.endif +x!= echo '0 || $${iV1} <= $${V42}: $x' >&2; echo + +# ${iV2:U2} expands to 2 +.if 0 || ${iV2:U2} < ${V42} +x= Ok +.else +x= Fail +.endif +x!= echo '0 || $${iV2:U2} < $${V42}: $x' >&2; echo + +# The right-hand side of the '&&' is irrelevant since the left-hand side +# already evaluates to false. Before cond.c 1.79 from 2020-07-09, it was +# expanded nevertheless, although with a small modification: undefined +# variables may be used in these expressions without generating an error. +.if defined(UNDEF) && ${UNDEF} != "undefined" +. error +.endif + +# TODO: Test each modifier to make sure it is skipped when it is irrelevant +# for the result. Since this test is already quite long, do that in another +# test. + +all: + @:;: |