do not throw when inspecting more complex union types

Bug: CESNET/netconf-cli#20 Reported-by: Michal Hažlinský <michal.hazlinsky@cesnet.cz> Change-Id: I21e5939c23dd82870bba8af7ca26d0db32339470
CESNET · Jan 22, 2024 · 5884eea · 5884eea
1 parent 1af87af
commit 5884eea
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Showing 2 changed files with 30 additions and 7 deletions.
diff --git a/src/Type.cpp b/src/Type.cpp
@@ -311,20 +311,24 @@ bool InstanceIdentifier::requireInstance() const
 /**
  * @brief Returns the types contained within this union.
  *
+ * Due to the libyang limitations, the returned types might not contain any parsed-type representation, and therefore
+ * even calling types::Type::name() on it could fail (possibly with a misleading exception
+ * "Context not created with libyang::ContextOptions::SetPrivParsed" even when the context *was* created with this
+ * option).
+ *
  * Wraps `lysc_type_union::types`
  */
 std::vector<Type> Union::types() const
 {
     auto types = reinterpret_cast<const lysc_type_union*>(m_type)->types;
     std::vector<Type> res;
-    if (m_typeParsed && LY_ARRAY_COUNT(types) != LY_ARRAY_COUNT(m_typeParsed->types)) {
-        throw std::logic_error("libyang-cpp internal error: LY_ARRAY_COUNT(lysc_type_union->types) = "
-                + std::to_string(LY_ARRAY_COUNT(types)) + ", LY_ARRAY_COUNT(lysp_type->types) = "
-                + std::to_string(LY_ARRAY_COUNT(m_typeParsed->types)) + ", lysp_type->name = " + m_typeParsed->name);
-    }
 
     for (size_t i = 0; i < LY_ARRAY_COUNT(types); i++) {
-        auto typeParsed = m_typeParsed ? &m_typeParsed->types[i] : nullptr;
+        // Some non-trivial union types, such as inet::host, have a different number of `lysc_type_union::types`
+        // vs. `lysp_type::types`. When that happens, then there's absolutely nothing that we can do; the parsed type
+        // info just isn't available anywhere with the current libyang.
+        auto typeParsed = m_typeParsed && LY_ARRAY_COUNT(types) == LY_ARRAY_COUNT(m_typeParsed->types) ?
+            &m_typeParsed->types[i] : nullptr;
         res.emplace_back(Type{types[i], typeParsed, m_ctx});
     }
 

diff --git a/tests/schema_node.cpp b/tests/schema_node.cpp
@@ -512,7 +512,7 @@ TEST_CASE("SchemaNode")
             REQUIRE(typeWithParsed.base() == libyang::LeafBaseType::String);
         }
 
-        DOCTEST_SUBCASE("union")
+        DOCTEST_SUBCASE("simple union")
         {
             auto types = ctx->findPath("/type_module:leafUnion").asLeaf().valueType().asUnion().types();
             REQUIRE(types.at(0).base() == libyang::LeafBaseType::String);
@@ -525,6 +525,25 @@ TEST_CASE("SchemaNode")
             REQUIRE(typesWithParsed.at(1).name() == "int32");
             REQUIRE(typesWithParsed.at(2).name() == "boolean");
         }
+
+        DOCTEST_SUBCASE("inet::host union")
+        {
+            ctx->parseModule(with_inet_types_module, libyang::SchemaFormat::YANG);
+            auto types = ctx->findPath("/with-inet-types:hostname").asLeaf().valueType().asUnion().types();
+            REQUIRE(types.size() == 3);
+            REQUIRE(types.at(0).base() == libyang::LeafBaseType::String);
+            REQUIRE(types.at(1).base() == libyang::LeafBaseType::String);
+            REQUIRE(types.at(2).base() == libyang::LeafBaseType::String);
+
+            ctxWithParsed->parseModule(with_inet_types_module, libyang::SchemaFormat::YANG);
+            auto typesWithParsed = ctxWithParsed->findPath("/with-inet-types:hostname").asLeaf().valueType().asUnion().types();
+            REQUIRE(typesWithParsed.size() == 3);
+            REQUIRE(typesWithParsed.at(0).base() == libyang::LeafBaseType::String);
+            REQUIRE(typesWithParsed.at(1).base() == libyang::LeafBaseType::String);
+            REQUIRE(typesWithParsed.at(2).base() == libyang::LeafBaseType::String);
+            // in libyang::types::Union::types() there are no types in the lysp_type::types`
+            REQUIRE_THROWS_AS(typesWithParsed.at(0).name(), libyang::ParsedInfoUnavailable);
+        }
     }
 
     DOCTEST_SUBCASE("Leaf::units")