xref: /src/usr.bin/make/unit-tests/cond-cmp-numeric-lt.mk

# $NetBSD: cond-cmp-numeric-lt.mk,v 1.2 2020/10/24 08:46:08 rillig Exp $
#
# Tests for numeric comparisons with the < operator in .if conditions.

# When both sides are equal, the < operator always yields false.
.if 1 < 1
.  error
.endif

# This comparison yields the same result, whether numeric or character-based.
.if 1 < 2
.else
.  error
.endif

.if 2 < 1
.  error
.endif

# If this comparison were character-based instead of numerical, the
# 5 would be > 14 since its first digit is greater.
.if 5 < 14
.else
.  error
.endif

.if 14 < 5
.  error
.endif

# Scientific notation is supported, as per strtod.
.if 2e7 < 1e8
.else
.  error
.endif

.if 1e8 < 2e7
.  error
.endif

# Floating pointer numbers can be compared as well.
# This might be tempting to use for version numbers, but there are a few pitfalls.
.if 3.141 < 111.222
.else
.  error
.endif

.if 111.222 < 3.141
.  error
.endif

# When parsed as a version number, 3.30 is greater than 3.7.
# Since make parses numbers as plain numbers, that leads to wrong results.
# Numeric comparisons are not suited for comparing version number.
.if 3.30 < 3.7
.else
.  error
.endif

.if 3.7 < 3.30
.  error
.endif

# As of 2020-08-23, numeric comparison is implemented as parsing both sides
# as double, and then performing a normal comparison.  The range of double is
# typically 16 or 17 significant digits, therefore these two numbers seem to
# be equal.
.if 1.000000000000000001 < 1.000000000000000002
.  error
.endif

all:
	@:;