[committed] libstdc++: Declutter std::optional and std:variant pretty printers [PR110944]

[committed] libstdc++: Declutter std::optional and std:variant pretty printers [PR110944]

[Jonathan Wakely]

Tested x86_64-linux. Pushed to trunk.

-- >8 --

As the PR says, including the template arguments in the GDB output of
these class templates can result in very long names, especially for
std::variant. You can use 'whatis' or other GDB commands to get details
of the type, we don't need to include it in the value.

We could consider including the type if it's not too long, but I think
consistency is better (and we already omit the template arguments for
std::vector and other class templates).

libstdc++-v3/ChangeLog:

	PR libstdc++/110944
	* python/libstdcxx/v6/printers.py (StdExpOptionalPrinter): Do
	not show template arguments.
	(StdVariantPrinter): Likewise.
	* testsuite/libstdc++-prettyprinters/compat.cc: Adjust expected
	output.
	* testsuite/libstdc++-prettyprinters/cxx17.cc: Likewise.
	* testsuite/libstdc++-prettyprinters/libfundts.cc: Likewise.
---
 libstdc++-v3/python/libstdcxx/v6/printers.py  |  3 +--
 .../libstdc++-prettyprinters/compat.cc        |  8 +++----
 .../libstdc++-prettyprinters/cxx17.cc         | 22 +++++++++----------
 .../libstdc++-prettyprinters/libfundts.cc     | 12 +++++-----
 4 files changed, 22 insertions(+), 23 deletions(-)

diff --git a/libstdc++-v3/python/libstdcxx/v6/printers.py b/libstdc++-v3/python/libstdcxx/v6/printers.py
index 0187c4b60e6..1a8017adb22 100644
--- a/libstdc++-v3/python/libstdcxx/v6/printers.py
+++ b/libstdc++-v3/python/libstdcxx/v6/printers.py
@@ -1343,7 +1343,7 @@ class StdExpOptionalPrinter(SingleObjContainerPrinter):
     def __init__ (self, typename, val):
         valtype = self._recognize (val.type.template_argument(0))
         typename = strip_versioned_namespace(typename)
-        self.typename = re.sub('^std::(experimental::|)(fundamentals_v\d::|)(.*)', r'std::\1\3<%s>' % valtype, typename, 1)
+        self.typename = re.sub('^std::(experimental::|)(fundamentals_v\d::|)(.*)', r'std::\1\3', typename, 1)
         payload = val['_M_payload']
         if self.typename.startswith('std::experimental'):
             engaged = val['_M_engaged']
@@ -1375,7 +1375,6 @@ class StdVariantPrinter(SingleObjContainerPrinter):
     def __init__(self, typename, val):
         alternatives = get_template_arg_list(val.type)
         self.typename = strip_versioned_namespace(typename)
-        self.typename = "%s<%s>" % (self.typename, ', '.join([self._recognize(alt) for alt in alternatives]))
         self.index = val['_M_index']
         if self.index >= len(alternatives):
             self.contained_type = None
diff --git a/libstdc++-v3/testsuite/libstdc++-prettyprinters/compat.cc b/libstdc++-v3/testsuite/libstdc++-prettyprinters/compat.cc
index 34022cf1459..acc20a30d8e 100644
--- a/libstdc++-v3/testsuite/libstdc++-prettyprinters/compat.cc
+++ b/libstdc++-v3/testsuite/libstdc++-prettyprinters/compat.cc
@@ -102,13 +102,13 @@ main()
   using std::optional;
 
   optional<int> o;
-// { dg-final { note-test o {std::optional<int> [no contained value]} } }
+// { dg-final { note-test o {std::optional [no contained value]} } }
   optional<bool> ob{false};
-// { dg-final { note-test ob {std::optional<bool> = {[contained value] = false}} } }
+// { dg-final { note-test ob {std::optional = {[contained value] = false}} } }
   optional<int> oi{5};
-// { dg-final { note-test oi {std::optional<int> = {[contained value] = 5}} } }
+// { dg-final { note-test oi {std::optional = {[contained value] = 5}} } }
   optional<void*> op{nullptr};
-// { dg-final { note-test op {std::optional<void *> = {[contained value] = 0x0}} } }
+// { dg-final { note-test op {std::optional = {[contained value] = 0x0}} } }
 
   __builtin_puts("");
   return 0;			// Mark SPOT
diff --git a/libstdc++-v3/testsuite/libstdc++-prettyprinters/cxx17.cc b/libstdc++-v3/testsuite/libstdc++-prettyprinters/cxx17.cc
index 3962a5e9b7e..eb8dc957a43 100644
--- a/libstdc++-v3/testsuite/libstdc++-prettyprinters/cxx17.cc
+++ b/libstdc++-v3/testsuite/libstdc++-prettyprinters/cxx17.cc
@@ -50,18 +50,18 @@ main()
 // { dg-final { note-test str "\"string\"" } }
 
   optional<int> o;
-// { dg-final { note-test o {std::optional<int> [no contained value]} } }
+// { dg-final { note-test o {std::optional [no contained value]} } }
   optional<bool> ob{false};
-// { dg-final { note-test ob {std::optional<bool> = {[contained value] = false}} } }
+// { dg-final { note-test ob {std::optional = {[contained value] = false}} } }
   optional<int> oi{5};
-// { dg-final { note-test oi {std::optional<int> = {[contained value] = 5}} } }
+// { dg-final { note-test oi {std::optional = {[contained value] = 5}} } }
   optional<void*> op{nullptr};
-// { dg-final { note-test op {std::optional<void *> = {[contained value] = 0x0}} } }
+// { dg-final { note-test op {std::optional = {[contained value] = 0x0}} } }
   optional<std::map<int, double>> om;
   om = std::map<int, double>{ {1, 2.}, {3, 4.}, {5, 6.} };
-// { dg-final { regexp-test om {std::optional<std::(__debug::)?map<int, double>> containing std::(__debug::)?map with 3 elements = {\[1\] = 2, \[3\] = 4, \[5\] = 6}} } }
+// { dg-final { regexp-test om {std::optional containing std::(__debug::)?map with 3 elements = {\[1\] = 2, \[3\] = 4, \[5\] = 6}} } }
   optional<std::string> os{ "stringy" };
-// { dg-final { note-test os {std::optional<std::string> = {[contained value] = "stringy"}} } }
+// { dg-final { note-test os {std::optional = {[contained value] = "stringy"}} } }
 
   any a;
 // { dg-final { note-test a {std::any [no contained value]} } }
@@ -83,18 +83,18 @@ main()
 
   struct S { operator int() { throw 42; }};
   variant<float, int, string_view> v0;
-// { dg-final { note-test v0 {std::variant<float, int, std::string_view> [index 0] = {0}} } }
+// { dg-final { note-test v0 {std::variant [index 0] = {0}} } }
   variant<float, int, string_view> v1{ 0.5f };
-// { dg-final { note-test v1 {std::variant<float, int, std::string_view> [index 0] = {0.5}} } }
+// { dg-final { note-test v1 {std::variant [index 0] = {0.5}} } }
   variant<float, X, string_view> v2;
   try {
     v2.emplace<1>(S());
   } catch (int) { }
-// { dg-final { note-test v2 {std::variant<float, X, std::string_view> [no contained value]} } }
+// { dg-final { note-test v2 {std::variant [no contained value]} } }
   variant<float, int, string_view> v3{ 3 };
-// { dg-final { note-test v3 {std::variant<float, int, std::string_view> [index 1] = {3}} } }
+// { dg-final { note-test v3 {std::variant [index 1] = {3}} } }
   variant<float, int, string_view> v4{ str };
-// { dg-final { note-test v4 {std::variant<float, int, std::string_view> [index 2] = {"string"}} } }
+// { dg-final { note-test v4 {std::variant [index 2] = {"string"}} } }
 
   map<int, string_view> m{ {1, "one"} };
   map<int, string_view>::node_type n0;
diff --git a/libstdc++-v3/testsuite/libstdc++-prettyprinters/libfundts.cc b/libstdc++-v3/testsuite/libstdc++-prettyprinters/libfundts.cc
index 29e8bc8f194..8f70f3fd151 100644
--- a/libstdc++-v3/testsuite/libstdc++-prettyprinters/libfundts.cc
+++ b/libstdc++-v3/testsuite/libstdc++-prettyprinters/libfundts.cc
@@ -42,18 +42,18 @@ main()
 // { dg-final { note-test str "\"string\"" } }
 
   optional<int> o;
-// { dg-final { note-test o {std::experimental::optional<int> [no contained value]} } }
+// { dg-final { note-test o {std::experimental::optional [no contained value]} } }
   optional<bool> ob{false};
-// { dg-final { note-test ob {std::experimental::optional<bool> = {[contained value] = false}} } }
+// { dg-final { note-test ob {std::experimental::optional = {[contained value] = false}} } }
   optional<int> oi{5};
-// { dg-final { note-test oi {std::experimental::optional<int> = {[contained value] = 5}} } }
+// { dg-final { note-test oi {std::experimental::optional = {[contained value] = 5}} } }
   optional<void*> op{nullptr};
-// { dg-final { note-test op {std::experimental::optional<void *> = {[contained value] = 0x0}} } }
+// { dg-final { note-test op {std::experimental::optional = {[contained value] = 0x0}} } }
   optional<std::map<int, double>> om;
   om = std::map<int, double>{ {1, 2.}, {3, 4.}, {5, 6.} };
-// { dg-final { regexp-test om {std::experimental::optional<std::(__debug::)?map<int, double>> containing std::(__debug::)?map with 3 elements = {\[1\] = 2, \[3\] = 4, \[5\] = 6}} } }
+// { dg-final { regexp-test om {std::experimental::optional containing std::(__debug::)?map with 3 elements = {\[1\] = 2, \[3\] = 4, \[5\] = 6}} } }
   optional<std::string> os{ "stringy" };
-// { dg-final { note-test os {std::experimental::optional<std::string> = {[contained value] = "stringy"}} } }
+// { dg-final { note-test os {std::experimental::optional = {[contained value] = "stringy"}} } }
 
   any a;
 // { dg-final { note-test a {std::experimental::any [no contained value]} } }
-- 
2.41.0