661 lines
21 KiB
C#
661 lines
21 KiB
C#
// Copyright Epic Games, Inc. All Rights Reserved.
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using System;
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using System.Collections.Generic;
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using System.Globalization;
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using System.Text;
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using EpicGames.Core;
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using EpicGames.UHT.Types;
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namespace EpicGames.UHT.Utils
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{
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static class UhtStringBuilderExtensions
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{
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/// <summary>
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/// String of tabs used to generate code with proper indentation
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/// </summary>
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public static StringView TabsString = new(new string('\t', 128));
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/// <summary>
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/// String of spaces used to generate code with proper indentation
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/// </summary>
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public static StringView SpacesString = new(new string(' ', 128));
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/// <summary>
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/// Names of meta data entries that will not appear in shipping builds for game code
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/// </summary>
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private static readonly HashSet<string> s_hiddenMetaDataNames = new(new string[]{ UhtNames.Comment, UhtNames.ToolTip }, StringComparer.OrdinalIgnoreCase);
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/// <summary>
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/// Append tabs to the builder
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="tabs">Number of tabs to insert</param>
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/// <returns>Destination builder</returns>
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/// <exception cref="ArgumentOutOfRangeException">Thrown if the number of tabs is out of range</exception>
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public static StringBuilder AppendTabs(this StringBuilder builder, int tabs)
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{
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if (tabs < 0 || tabs > TabsString.Length)
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{
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throw new ArgumentOutOfRangeException($"Number of tabs specified must be between 0 and {TabsString.Length - 1} inclusive");
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}
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else if (tabs > 0)
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{
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builder.Append(TabsString.Span[..tabs]);
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}
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return builder;
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}
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/// <summary>
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/// Append spaces to the builder
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="spaces">Number of spaces to insert</param>
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/// <returns>Destination builder</returns>
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/// <exception cref="ArgumentOutOfRangeException">Thrown if the number of spaces is out of range</exception>
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public static StringBuilder AppendSpaces(this StringBuilder builder, int spaces)
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{
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if (spaces < 0 || spaces > SpacesString.Length)
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{
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throw new ArgumentOutOfRangeException($"Number of spaces specified must be between 0 and {SpacesString.Length - 1} inclusive");
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}
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else if (spaces > 0)
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{
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builder.Append(SpacesString.Span[..spaces]);
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}
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return builder;
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}
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/// <summary>
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/// Append a name declaration to the builder
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="namePrefix">Name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendNameDecl(this StringBuilder builder, string? namePrefix, string name, string? nameSuffix)
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{
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return builder.Append(namePrefix).Append(name).Append(nameSuffix);
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}
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/// <summary>
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/// Append a name declaration to the builder
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="context">Property context used to get the name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendNameDecl(this StringBuilder builder, IUhtPropertyMemberContext context, string name, string nameSuffix)
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{
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return builder.AppendNameDecl(context.NamePrefix, name, nameSuffix);
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}
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/// <summary>
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/// Append a name definition to the builder
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="staticsName">Optional name of the statics block which will be output in the form of "StaticsName::"</param>
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/// <param name="namePrefix">Name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendNameDef(this StringBuilder builder, string? staticsName, string? namePrefix, string name, string? nameSuffix)
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{
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if (!String.IsNullOrEmpty(staticsName))
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{
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builder.Append(staticsName).Append("::");
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}
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return builder.AppendNameDecl(namePrefix, name, nameSuffix);
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}
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/// <summary>
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/// Append a name definition to the builder
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="context">Property context used to get the statics name and name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendNameDef(this StringBuilder builder, IUhtPropertyMemberContext context, string name, string nameSuffix)
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{
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return builder.AppendNameDef(context.StaticsName, context.NamePrefix, name, nameSuffix);
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}
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/// <summary>
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/// Append the meta data parameters. This is intended to be used as arguments to a function call.
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="type">Source type containing the meta data</param>
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/// <param name="staticsName">Optional name of the statics block which will be output in the form of "StaticsName::"</param>
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/// <param name="namePrefix">Name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <param name="metaNameSuffix">Suffix to be added to the meta data name</param>
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/// <returns>Destination builder</returns>
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private static StringBuilder AppendMetaDataParams(this StringBuilder builder, UhtType type, string? staticsName, string? namePrefix, string name, string? nameSuffix, string? metaNameSuffix)
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{
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if (!type.MetaData.IsEmpty())
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{
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return builder
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.Append("METADATA_PARAMS(")
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.Append("UE_ARRAY_COUNT(")
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.AppendNameDef(staticsName, namePrefix, name, nameSuffix).Append(metaNameSuffix)
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.Append("), ")
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.AppendNameDef(staticsName, namePrefix, name, nameSuffix).Append(metaNameSuffix)
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.Append(')');
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}
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else
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{
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return builder.Append("METADATA_PARAMS(0, nullptr)");
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}
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}
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/// <summary>
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/// Append the meta data parameters. This is intended to be used as arguments to a function call.
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="type">Source type containing the meta data</param>
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/// <param name="staticsName">Optional name of the statics block which will be output in the form of "StaticsName::"</param>
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/// <param name="name">Name</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendMetaDataParams(this StringBuilder builder, UhtType type, string? staticsName, string name)
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{
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return builder.AppendMetaDataParams(type, staticsName, null, name, null, null);
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}
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/// <summary>
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/// Append the meta data parameters. This is intended to be used as arguments to a function call.
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="property">Source type containing the meta data</param>
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/// <param name="context">Property context used to get the statics name and name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendMetaDataParams(this StringBuilder builder, UhtProperty property, IUhtPropertyMemberContext context, string name, string nameSuffix)
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{
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return builder.AppendMetaDataParams(property, null, context.NamePrefix, name, nameSuffix, context.MetaDataSuffix);
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}
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/// <summary>
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/// Append the meta data declaration.
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="type">Source type containing the meta data</param>
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/// <param name="namePrefix">Name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <param name="metaNameSuffix">Optional meta data name suffix</param>
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/// <param name="tabs">Number of tabs to indent</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendMetaDataDecl(this StringBuilder builder, UhtType type, string? namePrefix, string name, string? nameSuffix, string? metaNameSuffix, int tabs)
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{
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if (!type.MetaData.IsEmpty())
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{
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bool isPartOfEngine = type.Module.IsPartOfEngine;
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List<KeyValuePair<string, string>> sortedMetaData = type.MetaData.GetSorted();
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builder.AppendTabs(tabs).Append("static constexpr UECodeGen_Private::FMetaDataPairParam ").AppendNameDecl(namePrefix, name, nameSuffix).Append(metaNameSuffix).Append("[] = {\r\n");
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foreach (KeyValuePair<string, string> kvp in sortedMetaData)
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{
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bool restricted = !isPartOfEngine && s_hiddenMetaDataNames.Contains(kvp.Key);
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if (restricted)
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{
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builder.Append("#if !UE_BUILD_SHIPPING\r\n");
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}
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builder.AppendTabs(tabs + 1).Append("{ ").AppendUTF8LiteralString(kvp.Key).Append(", ").AppendUTF8LiteralString(kvp.Value).Append(" },\r\n");
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if (restricted)
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{
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builder.Append("#endif\r\n");
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}
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}
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builder.AppendTabs(tabs).Append("};\r\n");
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}
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return builder;
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}
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/// <summary>
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/// Append the meta data declaration
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="property">Source type containing the meta data</param>
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/// <param name="context">Property context used to get the statics name and name prefix</param>
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/// <param name="name">Name</param>
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/// <param name="nameSuffix">Optional name suffix</param>
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/// <param name="tabs">Number of tabs to indent</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendMetaDataDecl(this StringBuilder builder, UhtProperty property, IUhtPropertyMemberContext context, string name, string nameSuffix, int tabs)
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{
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return property.AppendMetaDataDecl(builder, context, name, nameSuffix, tabs);
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}
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/// <summary>
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/// Append the given text as a UTF8 encoded string
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="useText">If false, don't encode the text but include a nullptr</param>
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/// <param name="text">Text to include or an empty string if null.</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendUTF8LiteralString(this StringBuilder builder, bool useText, string? text)
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{
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if (!useText)
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{
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builder.Append("nullptr");
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}
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else if (text == null)
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{
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builder.Append("");
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}
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else
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{
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builder.AppendUTF8LiteralString(text);
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}
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return builder;
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}
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/// <summary>
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/// Append the given text as a UTF8 encoded string
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="text">Text to include or an empty string if null.</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendUTF8LiteralString(this StringBuilder builder, string? text)
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{
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if (text == null)
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{
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builder.Append("");
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}
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else
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{
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builder.AppendUTF8LiteralString(new StringView(text));
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}
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return builder;
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}
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/// <summary>
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/// Append the given text as a UTF8 encoded string
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="text">Text to be encoded</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendUTF8LiteralString(this StringBuilder builder, StringView text)
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{
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builder.Append('\"');
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ReadOnlySpan<char> span = text.Span;
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int length = span.Length;
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if (length > 0)
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{
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bool trailingHex = false;
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int index = 0;
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while (true)
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{
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// Scan forward looking for anything that can just be blindly copied
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int startIndex = index;
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while (index < length)
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{
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char cskip = span[index];
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if (cskip < 31 || cskip > 127 || cskip == '"' || cskip == '\\')
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{
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break;
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}
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++index;
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}
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// If we found anything
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if (startIndex < index)
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{
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// We close and open the literal here in order to ensure that successive hex characters aren't appended to the hex sequence, causing a different number
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if (trailingHex && UhtFCString.IsHexDigit(span[startIndex]))
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{
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builder.Append("\"\"");
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}
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builder.Append(span[startIndex..index]);
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}
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// We have either reached the end of the string, break
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if (index == length)
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{
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break;
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}
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// This character requires special processing
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char c = span[index++];
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switch (c)
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{
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case '\r':
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trailingHex = false;
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break;
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case '\n':
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trailingHex = false;
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builder.Append("\\n");
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break;
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case '\\':
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trailingHex = false;
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builder.Append("\\\\");
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break;
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case '\"':
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trailingHex = false;
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builder.Append("\\\"");
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break;
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default:
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if (c < 31)
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{
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trailingHex = true;
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builder.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", (uint)c);
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}
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else
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{
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trailingHex = false;
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if (Char.IsHighSurrogate(c))
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{
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if (index == length)
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{
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builder.Append('?');
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break;
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}
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char clow = span[index];
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if (Char.IsLowSurrogate(clow))
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{
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++index;
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builder.AppendEscapedUtf32((ulong)Char.ConvertToUtf32(c, clow));
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trailingHex = true;
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}
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else
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{
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builder.Append('?');
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}
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}
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else if (Char.IsLowSurrogate(c))
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{
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builder.Append('?');
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}
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else
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{
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builder.AppendEscapedUtf32(c);
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trailingHex = true;
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}
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}
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break;
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}
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}
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}
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builder.Append('\"');
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return builder;
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}
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/// <summary>
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/// Encode a single UTF32 value as UTF8 characters
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="c">Character to encode</param>
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/// <returns>Destination builder</returns>
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public static StringBuilder AppendEscapedUtf32(this StringBuilder builder, ulong c)
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{
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if (c < 0x80)
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{
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builder
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", c);
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}
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else if (c < 0x800)
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{
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builder
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0xC0 + (c >> 6))
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0x80 + (c & 0x3f));
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}
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else if (c < 0x10000)
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{
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builder
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0xE0 + (c >> 12))
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0x80 + ((c >> 6) & 0x3f))
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0x80 + (c & 0x3f));
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}
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else
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{
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builder
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0xF0 + (c >> 18))
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0x80 + ((c >> 12) & 0x3f))
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0x80 + ((c >> 6) & 0x3f))
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.Append("\\x").AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", 0x80 + (c & 0x3f));
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}
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return builder;
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}
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/// <summary>
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/// Append the given name of the class but always encode interfaces as the native interface name (i.e. "I...")
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="classObj">Class to append name</param>
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/// <returns>Destination builder</returns>
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/// <exception cref="NotImplementedException">Class has an unexpected class type</exception>
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public static StringBuilder AppendClassSourceNameOrInterfaceName(this StringBuilder builder, UhtClass classObj)
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{
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switch (classObj.ClassType)
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{
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case UhtClassType.Class:
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case UhtClassType.NativeInterface:
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return builder.Append(classObj.SourceName);
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case UhtClassType.Interface:
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return builder.Append('I').Append(classObj.SourceName[1..]);
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default:
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throw new NotImplementedException();
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}
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}
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/// <summary>
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/// Append the given name of the class but always encode interfaces as the native interface proxy name (i.e. "I...")
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="classObj">Class to append name</param>
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/// <returns>Destination builder</returns>
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/// <exception cref="NotImplementedException">Class has an unexpected class type</exception>
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public static StringBuilder AppendClassSourceNameOrInterfaceProxyName(this StringBuilder builder, UhtClass classObj)
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{
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switch (classObj.ClassType)
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{
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case UhtClassType.Class:
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return builder.Append(classObj.SourceName);
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case UhtClassType.NativeInterface:
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return builder.Append(classObj.SourceName).Append(UhtNames.VerseProxySuffix);
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case UhtClassType.Interface:
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return builder.Append('I').Append(classObj.SourceName[1..]).Append(UhtNames.VerseProxySuffix);
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default:
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throw new NotImplementedException();
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}
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}
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/// <summary>
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/// Given a verse name, encode it so it can be represented as an FName
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/// </summary>
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/// <param name="builder">Destination builder</param>
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/// <param name="name">Name to encode</param>
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/// <returns>Builder</returns>
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public static StringBuilder AppendEncodedVerseName(this StringBuilder builder, ReadOnlySpan<char> name)
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{
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bool isFirstChar = true;
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while (!name.IsEmpty)
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{
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char c = name[0];
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name = name[1..];
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if ((c >= 'a' && c <= 'z')
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|| (c >= 'A' && c <= 'Z')
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|| (c >= '0' && c <= '9' && !isFirstChar))
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{
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builder.Append(c);
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}
|
|
else if (c == '[' && !name.IsEmpty && name[0] == ']')
|
|
{
|
|
name = name[1..];
|
|
builder.Append("_K");
|
|
}
|
|
else if (c == '-' && !name.IsEmpty && name[0] == '>')
|
|
{
|
|
name = name[1..];
|
|
builder.Append("_T");
|
|
}
|
|
else if (c == '_')
|
|
{
|
|
builder.Append("__");
|
|
}
|
|
else if (c == '(')
|
|
{
|
|
builder.Append("_L");
|
|
}
|
|
else if (c == ',')
|
|
{
|
|
builder.Append("_M");
|
|
}
|
|
else if (c == ':')
|
|
{
|
|
builder.Append("_N");
|
|
}
|
|
else if (c == '^')
|
|
{
|
|
builder.Append("_P");
|
|
}
|
|
else if (c == '?')
|
|
{
|
|
builder.Append("_Q");
|
|
}
|
|
else if (c == ')')
|
|
{
|
|
builder.Append("_R");
|
|
}
|
|
else if (c == '\'')
|
|
{
|
|
builder.Append("_U");
|
|
}
|
|
else
|
|
{
|
|
builder.Append('_').AppendFormat(CultureInfo.InvariantCulture, "{0:x2}", (uint)c);
|
|
}
|
|
|
|
isFirstChar = false;
|
|
}
|
|
return builder;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Provides a cache of StringBuilders
|
|
/// </summary>
|
|
public class StringBuilderCache
|
|
{
|
|
|
|
/// <summary>
|
|
/// Cache of StringBuilders with large initial buffer sizes
|
|
/// </summary>
|
|
public static readonly StringBuilderCache Big = new(256, 256 * 1024);
|
|
|
|
/// <summary>
|
|
/// Cache of StringBuilders with small initial buffer sizes
|
|
/// </summary>
|
|
public static readonly StringBuilderCache Small = new(256, 1 * 1024);
|
|
|
|
/// <summary>
|
|
/// Capacity of the cache
|
|
/// </summary>
|
|
private readonly int _capacity;
|
|
|
|
/// <summary>
|
|
/// Initial buffer size for new StringBuilders. Resetting StringBuilders might result
|
|
/// in the initial chunk size being smaller.
|
|
/// </summary>
|
|
private readonly int _initialBufferSize;
|
|
|
|
/// <summary>
|
|
/// Stack of cached StringBuilders
|
|
/// </summary>
|
|
private readonly Stack<StringBuilder> _stack;
|
|
|
|
/// <summary>
|
|
/// Create a new StringBuilder cache
|
|
/// </summary>
|
|
/// <param name="capacity">Maximum number of StringBuilders to cache</param>
|
|
/// <param name="initialBufferSize">Initial buffer size for newly created StringBuilders</param>
|
|
public StringBuilderCache(int capacity, int initialBufferSize)
|
|
{
|
|
_capacity = capacity;
|
|
_initialBufferSize = initialBufferSize;
|
|
_stack = new Stack<StringBuilder>(_capacity);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Borrow a StringBuilder from the cache.
|
|
/// </summary>
|
|
/// <returns></returns>
|
|
public StringBuilder Borrow()
|
|
{
|
|
lock (_stack)
|
|
{
|
|
if (_stack.Count > 0)
|
|
{
|
|
return _stack.Pop();
|
|
}
|
|
}
|
|
|
|
return new StringBuilder(_initialBufferSize);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Return a StringBuilder to the cache
|
|
/// </summary>
|
|
/// <param name="builder">The builder being returned</param>
|
|
public void Return(StringBuilder builder)
|
|
{
|
|
// Sadly, clearing the builder (sets length to 0) will reallocate chunks.
|
|
builder.Clear();
|
|
lock (_stack)
|
|
{
|
|
if (_stack.Count < _capacity)
|
|
{
|
|
_stack.Push(builder);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Structure to automate the borrowing and returning of a StringBuilder.
|
|
/// Use some form of a "using" pattern.
|
|
/// </summary>
|
|
public readonly struct BorrowStringBuilder : IDisposable
|
|
{
|
|
|
|
/// <summary>
|
|
/// Owning cache
|
|
/// </summary>
|
|
private StringBuilderCache Cache { get; }
|
|
|
|
/// <summary>
|
|
/// Borrowed string builder
|
|
/// </summary>
|
|
public StringBuilder StringBuilder { get; }
|
|
|
|
/// <summary>
|
|
/// Borrow a string builder from the given cache
|
|
/// </summary>
|
|
/// <param name="cache">String builder cache</param>
|
|
public BorrowStringBuilder(StringBuilderCache cache)
|
|
{
|
|
Cache = cache;
|
|
StringBuilder = Cache.Borrow();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Return the string builder to the cache
|
|
/// </summary>
|
|
public void Dispose()
|
|
{
|
|
Cache.Return(StringBuilder);
|
|
}
|
|
}
|
|
}
|