From da194045ea1c306879abbb097a629b2d07722374 Mon Sep 17 00:00:00 2001
From: Mike Pilgrem <mpilgrem@users.noreply.github.com>
Date: Sat, 19 Sep 2026 16:08:20 +0100
Subject: [PATCH] Fix #6963 Support Cabal-3.18.1.0

---
 ChangeLog.md                     |  2 ++
 src/Stack/Setup.hs               |  4 ++--
 src/setup-shim/StackSetupShim.hs | 12 +++++++++++-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/ChangeLog.md b/ChangeLog.md
index d7d4ab87e5..6e010016c3 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -12,6 +12,8 @@ Behavior changes:
 
 Other enhancements:
 
+* Consider Cabal 3.18 to be a tested library and remove warnings.
+
 Bug fixes:
 
 ## v4.1.1
diff --git a/src/Stack/Setup.hs b/src/Stack/Setup.hs
index 54ce267092..83b83dab59 100644
--- a/src/Stack/Setup.hs
+++ b/src/Stack/Setup.hs
@@ -1095,9 +1095,9 @@ warnUnsupportedCompilerCabal cp didWarn = do
           , parens (style Shell "nightly-2018-03-13")
           , flow "or later specify such GHC versions."
           ]
-    | cabalVersion >= mkVersion [3, 17] && notifyIfCabalUntested ->
+    | cabalVersion >= mkVersion [3, 19] && notifyIfCabalUntested ->
         prettyWarnL
-          [ flow "Stack has not been tested with Cabal versions 3.18 and \
+          [ flow "Stack has not been tested with Cabal versions 3.20 and \
                  \above, but version"
           , fromString (versionString cabalVersion)
           , flow "was found, this may fail."
diff --git a/src/setup-shim/StackSetupShim.hs b/src/setup-shim/StackSetupShim.hs
index a87ec81fc9..dcb7ae0ed0 100644
--- a/src/setup-shim/StackSetupShim.hs
+++ b/src/setup-shim/StackSetupShim.hs
@@ -50,8 +50,12 @@ import Distribution.Types.PackageDescription ( PackageDescription )
 import Distribution.Utils.Path
          ( interpretSymbolicPathCWD, makeSymbolicPath, relativeSymbolicPath )
 #endif
+#if MIN_VERSION_Cabal(3,18,0)
+import Distribution.Verbosity ( Verbosity (..), defaultVerbosityHandles )
+#else
 import Distribution.Verbosity ( Verbosity )
 #endif
+#endif
 import Distribution.Verbosity ( flagToVerbosity )
 import Main
 import System.Environment ( getArgs )
@@ -88,7 +92,13 @@ stackReplHook arg1 arg2 = do
             "Unexpected happened running Setup.hs with " <>
             "stack-initial-build-steps, expected to parse Cabal verbosity: " <>
             msg1
-          Right verbosity -> do
+          Right verbosityFlags -> do
+            let verbosity =
+#if MIN_VERSION_Cabal(3,18,0)
+                  Verbosity verbosityFlags defaultVerbosityHandles
+#else
+                  verbosityFlags
+#endif             
             eFp <-
 #if MIN_VERSION_Cabal(3,14,0)
               findPackageDesc Nothing