[vcpkg] Use unique_ptr<> for paragraphs. Post-parser phase rework.

1 files changed, 59 insertions, 0 deletions

diff --git a/toolsrc/src/vcpkg_Parse.cpp b/toolsrc/src/vcpkg_Parse.cpp
new file mode 100644
index 000000000..b63ce41a9
--- /dev/null
+++ b/toolsrc/src/vcpkg_Parse.cpp
@@ -0,0 +1,59 @@
+#include "pch.h"
+
+#include "vcpkg_Checks.h"
+#include "vcpkg_Maps.h"
+#include "vcpkg_Parse.h"
+
+namespace vcpkg::Parse
+{
+    static Optional<std::string> get_field(const std::unordered_map<std::string, std::string>& fields,
+                                           const std::string& fieldname)
+    {
+        auto it = fields.find(fieldname);
+        if (it == fields.end())
+        {
+            return nullopt;
+        }
+
+        return it->second;
+    }
+
+    static Optional<std::string> remove_field(std::unordered_map<std::string, std::string>* fields,
+                                              const std::string& fieldname)
+    {
+        auto it = fields->find(fieldname);
+        if (it == fields->end())
+        {
+            return nullopt;
+        }
+
+        const std::string value = std::move(it->second);
+        fields->erase(it);
+        return value;
+    }
+
+    void ParagraphParser::required_field(const std::string& fieldname, std::string& out)
+    {
+        auto maybe_field = remove_field(&fields, fieldname);
+        if (auto field = maybe_field.get())
+            out = std::move(*field);
+        else
+            missing_fields.push_back(fieldname);
+    }
+    std::string ParagraphParser::optional_field(const std::string& fieldname)
+    {
+        return remove_field(&fields, fieldname).value_or("");
+    }
+    std::unique_ptr<ParseControlErrorInfo> ParagraphParser::error_info(const std::string& name) const
+    {
+        if (!fields.empty() || !missing_fields.empty())
+        {
+            auto err = std::make_unique<ParseControlErrorInfo>();
+            err->name = name;
+            err->extra_fields = Maps::extract_keys(fields);
+            err->missing_fields = std::move(missing_fields);
+            return err;
+        }
+        return nullptr;
+    }
+}