[gobject-introspection/ebassi/symbol-collision: 19/21] scanner: Add strict mode

[Emmanuele Bassi <ebassi src gnome org>]

commit 8ec097772459d67d5a7e888f5096f3f04a422ba1
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Wed Jun 16 17:02:25 2021 +0100

    scanner: Add strict mode
    
    To avoid introducing additional strictness onto unsuspecting libraries,
    we introduce a new mode: "strict".
    
    The strict mode is opt-in, and used to signal potential issues with the
    public API once exposed by language bindings, even when it's fully
    introspectable.

 docs/g-ir-scanner.1                 |  3 +++
 docs/website/tools/g-ir-scanner.rst |  4 ++++
 giscanner/message.py                | 18 ++++++++++++++++++
 giscanner/scannermain.py            |  8 +++++++-
 4 files changed, 32 insertions(+), 1 deletion(-)
---
diff --git a/docs/g-ir-scanner.1 b/docs/g-ir-scanner.1
index d25f321b..907baecb 100644
--- a/docs/g-ir-scanner.1
+++ b/docs/g-ir-scanner.1
@@ -57,6 +57,9 @@ Display warnings for public API which is not introspectable.
 .B \-\-warn\-error
 Make warnings be fatal errors.
 .TP
+.B \-\-strict
+Display warnings for strict introspectable API.
+.TP
 .BI \-\-format\fB= FORMAT
 This parameters decides which the resulting format will be used. The
 default value is gir.
diff --git a/docs/website/tools/g-ir-scanner.rst b/docs/website/tools/g-ir-scanner.rst
index e8df7457..47bbc2ff 100644
--- a/docs/website/tools/g-ir-scanner.rst
+++ b/docs/website/tools/g-ir-scanner.rst
@@ -42,6 +42,10 @@ OPTIONS
 --warn-error
     Make warnings be fatal errors.
 
+--strict
+    Display warnings for introspectable API that may present issues when
+    consumed by known language bindings.
+
 --format=FORMAT
     This parameters decides which the resulting format will be used. The
     default value is gir.
diff --git a/giscanner/message.py b/giscanner/message.py
index 24f1b7df..5b7bf685 100644
--- a/giscanner/message.py
+++ b/giscanner/message.py
@@ -102,6 +102,7 @@ class MessageLogger(object):
         self._output = output
         self._namespace = namespace
         self._enable_warnings = False
+        self._enable_strict = False
         self._warning_count = 0
 
     @classmethod
@@ -113,6 +114,17 @@ class MessageLogger(object):
     def enable_warnings(self, value):
         self._enable_warnings = bool(value)
 
+    @property
+    def warnings_enabled(self):
+        return self._enable_warnings
+
+    def enable_strict(self, value):
+        self._enable_strict = bool(value)
+
+    @property
+    def strict_enabled(self):
+        return self._enable_strict
+
     def get_warning_count(self):
         return self._warning_count
 
@@ -218,6 +230,12 @@ def error_node(node, text, context=None, positions=None):
     log_node(ERROR, node, text, context=context, positions=positions)
 
 
+def strict_node(node, text, context=None, positions=None):
+    ml = MessageLogger.get()
+    if ml.strict_enabled:
+        ml.log(WARNING, node, text, context=context, positions=positions)
+
+
 def warn_symbol(symbol, text):
     ml = MessageLogger.get()
     ml.log_symbol(WARNING, symbol, text)
diff --git a/giscanner/scannermain.py b/giscanner/scannermain.py
index 1124bc74..576f78ac 100644
--- a/giscanner/scannermain.py
+++ b/giscanner/scannermain.py
@@ -205,6 +205,9 @@ match the namespace prefix.""")
     parser.add_option('', "--warn-error",
                       action="store_true", dest="warn_fatal",
                       help="Turn warnings into fatal errors")
+    parser.add_option('', "--strict",
+                      action="store_true", dest="warn_strict", default=False,
+                      help="If true, enable strict warnings for introspection")
     parser.add_option("-v", "--verbose",
                       action="store_true", dest="verbose",
                       help="be verbose")
@@ -576,6 +579,8 @@ def scanner_main(args):
     logger = message.MessageLogger.get(namespace=namespace)
     if options.warn_all:
         logger.enable_warnings(True)
+    if options.warn_strict:
+        logger.enable_strict(True)
 
     transformer = create_transformer(namespace, options)
 
@@ -610,11 +615,12 @@ def scanner_main(args):
     final = IntrospectablePass(transformer, blocks)
     final.validate()
 
+    show_suppression = options.warn_all is False and options.warn_strict is False and options.quiet is False
     warning_count = logger.get_warning_count()
     if options.warn_fatal and warning_count > 0:
         message.fatal("warnings configured as fatal")
         return 1
-    elif warning_count > 0 and options.warn_all is False and options.quiet is False:
+    elif warning_count > 0 and show_suppression:
         print("g-ir-scanner: %s: warning: %d warnings suppressed "
               "(use --warn-all to see them)" %
               (transformer.namespace.name, warning_count, ))