From 63d8fdb71f3a2cbcd4555c092ec8704aabe3153b Mon Sep 17 00:00:00 2001
From: Michael Snoyman <michael@snoyman.com>
Date: Sat, 19 Sep 2015 22:59:59 +0300
Subject: [PATCH] Add hasUpperBound and hasLowerBound
This is useful for performing PVP bounds checking, especially for
tooling that wants to automate such dependency bounds. A demonstration
of this being used in practice is the --pvp-bounds flag for stack:
https://github.com/commercialhaskell/stack/commit/c774f9905b3b112f58fc3789dfb9c26389d33b24
---
Cabal/Distribution/Version.hs | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/Cabal/Distribution/Version.hs b/Cabal/Distribution/Version.hs
index 17c1fb7b1a..47a13146c6 100644
--- a/Cabal/Distribution/Version.hs
+++ b/Cabal/Distribution/Version.hs
@@ -44,6 +44,8 @@ module Distribution.Version (
simplifyVersionRange,
foldVersionRange,
foldVersionRange',
+ hasUpperBound,
+ hasLowerBound,
-- ** Modification
removeUpperBound,
@@ -805,3 +807,29 @@ instance Text VersionRange where
(">", LaterVersion),
(">=", orLaterVersion),
("==", ThisVersion) ]
+
+-- | Does the version range have an upper bound?
+--
+-- @since 1.24.0.0
+hasUpperBound :: VersionRange -> Bool
+hasUpperBound AnyVersion = False
+hasUpperBound (ThisVersion _) = True
+hasUpperBound (LaterVersion _) = False
+hasUpperBound (EarlierVersion _) = True
+hasUpperBound (WildcardVersion _) = True
+hasUpperBound (UnionVersionRanges x y) = hasUpperBound x && hasUpperBound y
+hasUpperBound (IntersectVersionRanges x y) = hasUpperBound x || hasUpperBound y
+hasUpperBound (VersionRangeParens x) = hasUpperBound x
+
+-- | Does the version range have a lower bound?
+--
+-- @since 1.24.0.0
+hasLowerBound :: VersionRange -> Bool
+hasLowerBound AnyVersion = False
+hasLowerBound (ThisVersion _) = True
+hasLowerBound (LaterVersion _) = True
+hasLowerBound (EarlierVersion _) = False
+hasLowerBound (WildcardVersion _) = True
+hasLowerBound (UnionVersionRanges x y) = hasLowerBound x && hasLowerBound y
+hasLowerBound (IntersectVersionRanges x y) = hasLowerBound x || hasLowerBound y
+hasLowerBound (VersionRangeParens x) = hasLowerBound x
--
GitLab