GHCi: Include a note in the hint to expose a hidden package

Test Plan: validate

Reviewers: bgamari, RyanGlScott, osa1

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

GHC Trac Issues: #15055

Differential Revision: https://phabricator.haskell.org/D4669

compiler/main/Finder.hs

@@ -678,7 +678,8 @@ cantFindErr cannot_find _ dflags mod_name find_result
          = let pkg = expectJust "pkg_hidden" (lookupPackage dflags pkgid)
            in text "You can run" <+>
               quotes (text ":set -package " <> ppr (packageName pkg)) <+>
-              text "to expose it."
+              text "to expose it." $$
+              text "(Note: this unloads all the modules in the current scope.)"
 
     mod_hidden pkg =
         text "it is a hidden module in the package" <+> quotes (ppr pkg)

testsuite/tests/ghci/should_fail/T15055.stderr

@@ -3,3 +3,4 @@
     Could not find module ‘GHC’
     It is a member of the hidden package ‘ghc-8.5’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)

testsuite/tests/package/package01e.stderr

@@ -3,10 +3,12 @@ package01e.hs:2:1: error:
     Could not find module ‘Data.Map’
     It is a member of the hidden package ‘containers-0.5.11.0’.
     You can run ‘:set -package containers’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.
 
 package01e.hs:3:1: error:
     Could not find module ‘Data.IntMap’
     It is a member of the hidden package ‘containers-0.5.11.0’.
     You can run ‘:set -package containers’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.

testsuite/tests/package/package06e.stderr

@@ -3,10 +3,12 @@ package06e.hs:2:1: error:
     Could not find module ‘HsTypes’
     It is a member of the hidden package ‘ghc-8.1’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.
 
 package06e.hs:3:1: error:
     Could not find module ‘UniqFM’
     It is a member of the hidden package ‘ghc-8.1’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.

testsuite/tests/package/package07e.stderr

@@ -8,16 +8,19 @@ package07e.hs:3:1: error:
     Could not find module ‘HsTypes’
     It is a member of the hidden package ‘ghc-8.5’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.
 
 package07e.hs:4:1: error:
     Could not find module ‘HsUtils’
     It is a member of the hidden package ‘ghc-8.5’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.
 
 package07e.hs:5:1: error:
     Could not find module ‘UniqFM’
     It is a member of the hidden package ‘ghc-8.5’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.

testsuite/tests/package/package08e.stderr

@@ -8,16 +8,19 @@ package08e.hs:3:1: error:
     Could not find module ‘HsTypes’
     It is a member of the hidden package ‘ghc-8.5’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.
 
 package08e.hs:4:1: error:
     Could not find module ‘HsUtils’
     It is a member of the hidden package ‘ghc-8.5’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.
 
 package08e.hs:5:1: error:
     Could not find module ‘UniqFM’
     It is a member of the hidden package ‘ghc-8.5’.
     You can run ‘:set -package ghc’ to expose it.
+    (Note: this unloads all the modules in the current scope.)
     Use -v to see a list of the files searched for.

testsuite/tests/plugins/T11244.stderr

 <command line>: Could not find module ‘RuleDefiningPlugin’
 It is a member of the hidden package ‘rule-defining-plugin-0.1’.
 You can run ‘:set -package rule-defining-plugin’ to expose it.
+(Note: this unloads all the modules in the current scope.)
 Use -v to see a list of the files searched for.