TemplateHaskellQuotes: Allow nested splices

There is no issue with nested splices as they do not require any compile
time code execution. All execution is delayed until the top-level
splice.

9 files changed, 54 insertions, 3 deletions

diff --git a/testsuite/tests/quotes/TH_double_splice.hs b/testsuite/tests/quotes/TH_double_splice.hs
new file mode 100644
index 0000000000..d8a0faeeae
--- /dev/null
+++ b/testsuite/tests/quotes/TH_double_splice.hs
@@ -0,0 +1,7 @@
+{-# LANGUAGE TemplateHaskellQuotes #-}
+module TH_double_splice where
+
+-- Should be a compile time error as TemplateHaskell is not enabled.
+
+foo = [| $($(error "should not happen")) |]
+
diff --git a/testsuite/tests/quotes/TH_double_splice.stderr b/testsuite/tests/quotes/TH_double_splice.stderr
new file mode 100644
index 0000000000..34cb933a1d
--- /dev/null
+++ b/testsuite/tests/quotes/TH_double_splice.stderr
@@ -0,0 +1,7 @@
+
+TH_double_splice.hs:6:12: error:
+    • Top-level splices are not permitted without TemplateHaskell
+    • In the untyped splice: $(error "should not happen")
+      In the untyped splice: $($(error "should not happen"))
+      In the Template Haskell quotation
+        [| $($(error "should not happen")) |]
diff --git a/testsuite/tests/quotes/TH_nested_splice.hs b/testsuite/tests/quotes/TH_nested_splice.hs
new file mode 100644
index 0000000000..811aa5e426
--- /dev/null
+++ b/testsuite/tests/quotes/TH_nested_splice.hs
@@ -0,0 +1,11 @@
+{-# LANGUAGE TemplateHaskellQuotes #-}
+{-# LANGUAGE NoMonomorphismRestriction #-}
+module TH_nested_splice where
+
+a = [| 5 |]
+
+b = [| $(a) |]
+
+c = [|| 5 ||]
+
+d = [|| $$(c) ||]
diff --git a/testsuite/tests/quotes/TH_top_splice.hs b/testsuite/tests/quotes/TH_top_splice.hs
new file mode 100644
index 0000000000..a7092bfd9d
--- /dev/null
+++ b/testsuite/tests/quotes/TH_top_splice.hs
@@ -0,0 +1,7 @@
+{-# LANGUAGE TemplateHaskellQuotes #-}
+module TH_top_splice where
+
+-- Should be a compile time error as TemplateHaskell is not enabled.
+
+foo = $([| 1 |])
+
diff --git a/testsuite/tests/quotes/TH_top_splice.stderr b/testsuite/tests/quotes/TH_top_splice.stderr
new file mode 100644
index 0000000000..8ca30c2426
--- /dev/null
+++ b/testsuite/tests/quotes/TH_top_splice.stderr
@@ -0,0 +1,4 @@
+
+TH_top_splice.hs:6:7: error:
+    • Top-level splices are not permitted without TemplateHaskell
+    • In the untyped splice: $([| 1 |])
diff --git a/testsuite/tests/quotes/TTH_top_splice.hs b/testsuite/tests/quotes/TTH_top_splice.hs
new file mode 100644
index 0000000000..53b85434de
--- /dev/null
+++ b/testsuite/tests/quotes/TTH_top_splice.hs
@@ -0,0 +1,8 @@
+{-# LANGUAGE TemplateHaskellQuotes #-}
+module TTH_top_splice where
+
+-- Should be a compile time error as TemplateHaskell is not enabled.
+
+qux = $$([|| 1 ||])
+
+
diff --git a/testsuite/tests/quotes/TTH_top_splice.stderr b/testsuite/tests/quotes/TTH_top_splice.stderr
new file mode 100644
index 0000000000..ef659c21d8
--- /dev/null
+++ b/testsuite/tests/quotes/TTH_top_splice.stderr
@@ -0,0 +1,4 @@
+
+TTH_top_splice.hs:6:7: error:
+    • Top-level splices are not permitted without TemplateHaskell
+    • In the typed splice: $$([|| 1 ||])
diff --git a/testsuite/tests/quotes/all.T b/testsuite/tests/quotes/all.T
index a10da1046f..46f53bce6a 100644
--- a/testsuite/tests/quotes/all.T
+++ b/testsuite/tests/quotes/all.T
@@ -30,3 +30,7 @@ test('TH_repE3', normal, compile, [''])
 test('TH_abstractFamily', normal, compile_fail, [''])
 test('TH_localname', normal, compile_fail, [''])
 test('TH_typed_csp', normal, compile, [''])
+test('TH_nested_splice', normal, compile, [''])
+test('TH_top_splice', normal, compile_fail, [''])
+test('TTH_top_splice', normal, compile_fail, [''])
+test('TH_double_splice', normal, compile_fail, [''])
diff --git a/testsuite/tests/safeHaskell/safeLanguage/SafeLang12.stderr b/testsuite/tests/safeHaskell/safeLanguage/SafeLang12.stderr
index 55aa3a5a6c..c7923a0403 100644
--- a/testsuite/tests/safeHaskell/safeLanguage/SafeLang12.stderr
+++ b/testsuite/tests/safeHaskell/safeLanguage/SafeLang12.stderr
@@ -8,6 +8,5 @@ SafeLang12_B.hs:2:14: warning:
 [2 of 3] Compiling SafeLang12_B     ( SafeLang12_B.hs, SafeLang12_B.o )
 [3 of 3] Compiling Main             ( SafeLang12.hs, SafeLang12.o )
 
-SafeLang12.hs:8:1: error:
-    parse error on input ‘$’
-    Perhaps you intended to use TemplateHaskell
+SafeLang12.hs:1:1: error:
+    Top-level splices are not permitted without TemplateHaskell