incremental parsing example and tests

danielaparker · Nov 11, 2024 · b8bea86 · b8bea86
1 parent 6ea30f2
commit b8bea86
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Showing 5 changed files with 45 additions and 57 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,7 +1,7 @@
 0.179.0 (on master)
 -------
 
-Changes:
+Changes to basic_json::operator[]:
 
 - Removed `basic_json` proxy type. The rationale for this change is given in #315.
 

diff --git a/examples/src/json_parser_examples.cpp b/examples/src/json_parser_examples.cpp
@@ -8,7 +8,9 @@
 
 using namespace jsoncons;
 
-void incremental_parsing_example1()
+#if JSONCONS_VERSION_MAJOR == 0 && JSONCONS_VERSION_MINOR < 179
+
+void incremental_parsing_example()
 {
     jsoncons::json_decoder<json> decoder;
     json_parser parser;
@@ -37,63 +39,48 @@ void incremental_parsing_example1()
     }
 }
 
-void incremental_parsing_example2()
-{
-    jsoncons::json_decoder<json> decoder;
-    json_parser parser;
-    try
-    {
-        parser.update("10");
-        parser.parse_some(decoder);
-        std::cout << "(1) done: " << std::boolalpha << parser.done() << ", source_exhausted: " << parser.source_exhausted() << "\n\n";
-
-        parser.update(".5");
-        parser.parse_some(decoder); // This is the end, but the parser can't tell
-        std::cout << "(2) done: " << std::boolalpha << parser.done() << ", source_exhausted: " << parser.source_exhausted() << "\n\n";
+#else
 
-        parser.finish_parse(decoder); // Indicates that this is the end
-        std::cout << "(3) done: " << std::boolalpha << parser.done() << ", source_exhausted: " << parser.source_exhausted() << "\n\n";
-
-        parser.check_done(); // Checks if there are any unconsumed 
-                             // non-whitespace characters in the input
-        std::cout << "(4) done: " << std::boolalpha << parser.done() << ", source_exhausted: " << parser.source_exhausted() << "\n\n";
+void incremental_parsing_example()
+{
+    std::vector<std::string> chunks = {"[fal", "se,", "9", "0", "]"};
+    std::size_t index = 0;
 
-        json j = decoder.get_result();
-        std::cout << "(5) " << j << "\n";
-    }
-    catch (const ser_error& e)
+    auto read_chunk = [&](jsoncons::parser_input& input, std::error_code& /*ec*/) -> bool
     {
-        std::cout << e.what() << std::endl;
-    }
-}
+        if (index < chunks.size())
+        {
+            input.update(chunks[index].data(), chunks[index].size());
+            ++index;
+            return true;
+        }
+        else
+        {
+            return false;
+        }
+    };
 
-void incremental_parsing_example3()
-{
     jsoncons::json_decoder<json> decoder;
-    json_parser parser;
+    json_parser parser{read_chunk};
+
+    parser.reset();
     try
     {
-        parser.update("[10");
         parser.parse_some(decoder);
-        std::cout << "(1) done: " << std::boolalpha << parser.done() << ", source_exhausted: " << parser.source_exhausted() << "\n\n";
-
-        parser.update(".5]{}");
-        parser.parse_some(decoder); // The parser reaches the end at ']'
-        std::cout << "(2) done: " << std::boolalpha << parser.done() << ", source_exhausted: " << parser.source_exhausted() << "\n\n";
-
-        parser.finish_parse(decoder); // Indicates that this is the end
-        std::cout << "(3) done: " << std::boolalpha << parser.done() << ", source_exhausted: " << parser.source_exhausted() << "\n\n";
+        parser.finish_parse(decoder);
+        parser.check_done();
 
-        parser.check_done(); // Checks if there are any unconsumed 
-                             // non-whitespace characters in the input
-                             // (there are)
+        json j = decoder.get_result();
+        std::cout << j << "\n\n";
     }
     catch (const ser_error& e)
     {
-        std::cout << "(4) " << e.what() << std::endl;
+        std::cout << e.what() << std::endl;
     }
 }
 
+#endif
+
 void parse_nan_replacement_example()
 {
     std::string s = R"(
@@ -140,10 +127,9 @@ void parse_nan_replacement_example()
 int main()
 {
     std::cout << "\njson_parser examples\n\n";
-    incremental_parsing_example1();
-    incremental_parsing_example2();
-    incremental_parsing_example3();
-    parse_nan_replacement_example();
+
+    incremental_parsing_example();
+    //parse_nan_replacement_example();
 
     std::cout << std::endl;
 }

diff --git a/include/jsoncons/config/version.hpp b/include/jsoncons/config/version.hpp
@@ -10,7 +10,7 @@
 #include <iostream>
 
 #define JSONCONS_VERSION_MAJOR 0
-#define JSONCONS_VERSION_MINOR 178
+#define JSONCONS_VERSION_MINOR 179
 #define JSONCONS_VERSION_PATCH 0
 
 namespace jsoncons {

diff --git a/include/jsoncons/json_parser.hpp b/include/jsoncons/json_parser.hpp
@@ -606,20 +606,18 @@ class basic_json_parser : public ser_context, public virtual basic_parser_input<
             more_ = false;
             return;
         }
-        const char_type* local_input_end = input_end_;
 
-        if (input_ptr_ == local_input_end && more_)
+        if (input_ptr_ == input_end_ && more_)
         {
-            if (input_ptr_ == local_input_end)
+            if (input_ptr_ == input_end_)
             {
                 chunk_rdr_->read_chunk(*this, ec);
                 if (ec)
                 {
                     return;
                 }
-                local_input_end = input_end_;
             }
-            if (input_ptr_ == local_input_end)
+            if (input_ptr_ == input_end_)
             {
                 switch (state_)
                 {
@@ -647,13 +645,12 @@ class basic_json_parser : public ser_context, public virtual basic_parser_input<
 
         while (more_)
         {
-            if (input_ptr_ == local_input_end)
+            if (input_ptr_ == input_end_)
             {
                 if (!chunk_rdr_->read_chunk(*this, ec))
                 {
                     break;
                 }
-                local_input_end = input_end_;
             }
 
             switch (state_)

diff --git a/test/corelib/src/json_parser_tests.cpp b/test/corelib/src/json_parser_tests.cpp
@@ -235,7 +235,7 @@ TEST_CASE("test_incremental_parsing")
 {
     SECTION("Array of strings")
     {
-        std::vector<std::string> chunks = {"[fal", "se]"};
+        std::vector<std::string> chunks = {"[fal", "se, ", "t", "rue", ", null", ",", "1", "234", ",\"Hello ", "World\"", "]"};
         std::size_t index = 0;
 
         auto read_chunk = [&](jsoncons::parser_input& input, std::error_code& /*ec*/) -> bool
@@ -265,7 +265,12 @@ TEST_CASE("test_incremental_parsing")
 
         json j = decoder.get_result();
         REQUIRE(j.is_array());
+        REQUIRE(j.size() == 5);
         CHECK_FALSE(j[0].as<bool>());
+        CHECK(j[1].as<bool>());
+        CHECK(j[2].is_null());
+        CHECK(j[3].as<int>() == 1234);
+        CHECK(j[4].as<std::string>() == "Hello World");
     }
 }