From 43f20ce4e8a773ff57d2badf575ac86e8e7549d3 Mon Sep 17 00:00:00 2001
From: sof <unknown>
Date: Sat, 6 Feb 1999 16:00:47 +0000
Subject: [PATCH] [project @ 1999-02-06 16:00:43 by sof] Added two new
(read.show) regression tests for derived Read&Show instances.
---
ghc/tests/deriving/should_run/drvrun002.hs | 17 +++++++++++
.../deriving/should_run/drvrun002.stdout | 2 ++
ghc/tests/deriving/should_run/drvrun003.hs | 30 +++++++++++++++++++
.../deriving/should_run/drvrun003.stdout | 3 ++
4 files changed, 52 insertions(+)
create mode 100644 ghc/tests/deriving/should_run/drvrun002.hs
create mode 100644 ghc/tests/deriving/should_run/drvrun002.stdout
create mode 100644 ghc/tests/deriving/should_run/drvrun003.hs
create mode 100644 ghc/tests/deriving/should_run/drvrun003.stdout
diff --git a/ghc/tests/deriving/should_run/drvrun002.hs b/ghc/tests/deriving/should_run/drvrun002.hs
new file mode 100644
index 000000000000..26497bd32c9f
--- /dev/null
+++ b/ghc/tests/deriving/should_run/drvrun002.hs
@@ -0,0 +1,17 @@
+-- !!! Deriving Show/Read for type with labelled fields.
+-- (based on a Hugs bug report.)
+module Main(main) where
+
+data Options =
+ Options { s :: OptionKind }
+ deriving (Show, Read)
+
+data OptionKind =
+ SpecialOptions { test :: Int }
+ deriving (Show, Read)
+
+x = Options{s=SpecialOptions{test=42}}
+
+main = do
+ print x
+ print ((read (show x))::Options)
diff --git a/ghc/tests/deriving/should_run/drvrun002.stdout b/ghc/tests/deriving/should_run/drvrun002.stdout
new file mode 100644
index 000000000000..183c2135b674
--- /dev/null
+++ b/ghc/tests/deriving/should_run/drvrun002.stdout
@@ -0,0 +1,2 @@
+Options{s=(SpecialOptions{test=42})}
+Options{s=(SpecialOptions{test=42})}
diff --git a/ghc/tests/deriving/should_run/drvrun003.hs b/ghc/tests/deriving/should_run/drvrun003.hs
new file mode 100644
index 000000000000..bb7486159e45
--- /dev/null
+++ b/ghc/tests/deriving/should_run/drvrun003.hs
@@ -0,0 +1,30 @@
+-- !!! Deriving Show/Read for nullary constructors.
+module Main(main) where
+
+data A = B | C deriving ( Show, Read )
+
+data Opt = N | Y A deriving (Show, Read)
+
+x = Y B
+
+{-
+ If the Haskell report's specification of how Show instances
+ are to be derived is followed to the letter, the code for
+ a nullary constructor would put parens around the constructor
+ when (showsPrec 10) is used. This would cause
+
+ Y A
+
+ to be showed as
+
+ Y (A)
+
+ Overkill, so ghc's derived Show code treats nullary
+ constructors specially.
+-}
+
+main = do
+ print x
+ print ((read (show x))::Opt)
+ print ((read "Y (B)")::Opt)
+
diff --git a/ghc/tests/deriving/should_run/drvrun003.stdout b/ghc/tests/deriving/should_run/drvrun003.stdout
new file mode 100644
index 000000000000..584cfcd5cede
--- /dev/null
+++ b/ghc/tests/deriving/should_run/drvrun003.stdout
@@ -0,0 +1,3 @@
+Y B
+Y B
+Y B
--
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