fixing docstrings for cppstd (#16341)

conan/tools/build/cppstd.py

@@ -11,12 +11,7 @@ def check_min_cppstd(conanfile, cppstd, gnu_extensions=False):
         In case the current cppstd doesn't fit the minimal version required
         by cppstd, a ConanInvalidConfiguration exception will be raised.
 
-        1. If settings.compiler.cppstd, the tool will use settings.compiler.cppstd to compare
-        2. It not settings.compiler.cppstd, the tool will use compiler to compare (reading the
-           default from cppstd_default)
-        3. If not settings.compiler is present (not declared in settings) will raise because it
-           cannot compare.
-        4. If can not detect the default cppstd for settings.compiler, a exception will be raised.
+        settings.compiler.cppstd must be defined, otherwise ConanInvalidConfiguration is raised
 
     :param conanfile: The current recipe object. Always use ``self``.
     :param cppstd: Minimal cppstd version required
@@ -31,12 +26,7 @@ def check_max_cppstd(conanfile, cppstd, gnu_extensions=False):
         In case the current cppstd doesn't fit the maximum version required
         by cppstd, a ConanInvalidConfiguration exception will be raised.
 
-        1. If settings.compiler.cppstd, the tool will use settings.compiler.cppstd to compare
-        2. It not settings.compiler.cppstd, the tool will use compiler to compare (reading the
-           default from cppstd_default)
-        3. If not settings.compiler is present (not declared in settings) will raise because it
-           cannot compare.
-        4. If can not detect the default cppstd for settings.compiler, a exception will be raised.
+        settings.compiler.cppstd must be defined, otherwise ConanInvalidConfiguration is raised
 
     :param conanfile: The current recipe object. Always use ``self``.
     :param cppstd: Maximum cppstd version required
@@ -126,12 +116,7 @@ def _check_cppstd(conanfile, cppstd, comparator, gnu_extensions):
         In case the current cppstd doesn't fit the maximum version required
         by cppstd, a ConanInvalidConfiguration exception will be raised.
 
-        1. If settings.compiler.cppstd, the tool will use settings.compiler.cppstd to compare
-        2. It not settings.compiler.cppstd, the tool will use compiler to compare (reading the
-           default from cppstd_default)
-        3. If not settings.compiler is present (not declared in settings) will raise because it
-           cannot compare.
-        4. If can not detect the default cppstd for settings.compiler, a exception will be raised.
+        settings.compiler.cppstd must be defined, otherwise ConanInvalidConfiguration is raised
 
     :param conanfile: The current recipe object. Always use ``self``.
     :param cppstd: Required cppstd version.
@@ -257,6 +242,7 @@ def _mcst_lcc_supported_cppstd(version):
 
     return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20"]
 
+
 def _qcc_supported_cppstd(version):
     """
     [98, gnu98, 11, gnu11, 14, gnu14, 17, gnu17]