Merge pull request #2178 from ivan-mogilko/361--trivialpreprocelse

Basic support for "#else" preprocessor in AGS script
adventuregamestudio · Oct 15, 2023 · 1ca7622 · 1ca7622
2 parents 8f7897c + 0056d83
commit 1ca7622
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Showing 6 changed files with 128 additions and 5 deletions.
diff --git a/Compiler/preproc/preprocessor.cpp b/Compiler/preproc/preprocessor.cpp
@@ -87,6 +87,9 @@ namespace Preprocessor {
                 case ErrorCode::IfWithoutEndIf:
                     cc_error("Missing #endif");
                     break;
+                case ErrorCode::ElseIfWithoutIf:
+                    cc_error("#else has no matching #if");
+                    break;
                 case ErrorCode::MacroDoesNotExist:
                 case ErrorCode::MacroAlreadyExists:
                 case ErrorCode::MacroNameInvalid:
@@ -114,7 +117,7 @@ namespace Preprocessor {
 
         bool includeCodeBlock = true;
 
-        if ((!_conditionalStatements.empty()) && !_conditionalStatements.back())
+        if ((!_conditionalStatements.empty()) && !_conditionalStatements.top())
         {
             includeCodeBlock = false;
         }
@@ -140,12 +143,12 @@ namespace Preprocessor {
             }
         }
 
-        _conditionalStatements.push_back(includeCodeBlock);
+        _conditionalStatements.push(includeCodeBlock);
     }
 
     bool Preprocessor::DeletingCurrentLine()
     {
-        return ((!_conditionalStatements.empty()) && !_conditionalStatements.back());
+        return ((!_conditionalStatements.empty()) && !_conditionalStatements.top());
     }
 
     String Preprocessor::GetNextWord(String &text, bool trimText, bool includeDots) {
@@ -231,11 +234,25 @@ namespace Preprocessor {
         {
             ProcessConditionalDirective(directive, line);
         }
+        else if (directive == "else")
+        {
+            if (!_conditionalStatements.empty())
+            {
+                // Negate previous condition
+                bool prev_value = _conditionalStatements.top();
+                _conditionalStatements.pop();
+                _conditionalStatements.push(!prev_value);
+            }
+            else
+            {
+                LogError(ErrorCode::ElseIfWithoutIf);
+            }
+        }
         else if (directive == "endif")
         {
             if (!_conditionalStatements.empty())
             {
-                _conditionalStatements.pop_back();
+                _conditionalStatements.pop();
             }
             else
             {

diff --git a/Compiler/preproc/preprocessor.h b/Compiler/preproc/preprocessor.h
@@ -1,3 +1,4 @@
+#include <stack>
 #include "script/cs_parser_common.h"
 #include "script/cc_macrotable.h"
 #include "util/string.h"
@@ -17,6 +18,7 @@ namespace Preprocessor {
         UserDefinedError,
         EndIfWithoutIf,
         IfWithoutEndIf,
+        ElseIfWithoutIf,
         InvalidVersionNumber,
         UnterminatedString
     };
@@ -28,7 +30,7 @@ namespace Preprocessor {
         int _lineNumber;
         String _scriptName;
         Version _applicationVersion;
-        std::vector<bool> _conditionalStatements = std::vector<bool>();
+        std::stack<bool> _conditionalStatements;
 
         static void LogError(ErrorCode error, const String &message = nullptr);
 

diff --git a/Compiler/test/preprocessor_test.cpp b/Compiler/test/preprocessor_test.cpp
@@ -303,6 +303,68 @@ Display("This does");
 }
 
 
+TEST(Preprocess, IfDefElse) {
+    Preprocessor pp = Preprocessor();
+    const char* inpl = R"EOS(
+#define FOO
+#ifdef FOO
+Display("This displays!");
+#else
+Display("This doesn't");
+#endif
+#ifndef FOO
+Display("This doesn't");
+#else
+Display("This displays!");
+#endif
+#undef FOO
+#ifdef FOO
+Display("This doesn't");
+#else
+Display("This displays!");
+#endif
+#ifndef FOO
+Display("This displays!");
+#else
+Display("This doesn't");
+#endif
+)EOS";
+
+    clear_error();
+    String res = pp.Preprocess(inpl, "ScriptIfDefElse");
+
+    EXPECT_STREQ(last_seen_cc_error(), "");
+
+    std::vector<AGSString> lines = SplitLines(res);
+    ASSERT_EQ(lines.size(), 25);
+
+    ASSERT_STREQ(lines[0].GetCStr(), "\"__NEWSCRIPTSTART_ScriptIfDefElse\"");
+    ASSERT_STREQ(lines[1].GetCStr(), "");
+    ASSERT_STREQ(lines[2].GetCStr(), "");
+    ASSERT_STREQ(lines[3].GetCStr(), "");
+    ASSERT_STREQ(lines[4].GetCStr(), "Display(\"This displays!\");");
+    ASSERT_STREQ(lines[5].GetCStr(), "");
+    ASSERT_STREQ(lines[6].GetCStr(), "");
+    ASSERT_STREQ(lines[7].GetCStr(), "");
+    ASSERT_STREQ(lines[8].GetCStr(), "");
+    ASSERT_STREQ(lines[9].GetCStr(), "");
+    ASSERT_STREQ(lines[10].GetCStr(), "");
+    ASSERT_STREQ(lines[11].GetCStr(), "Display(\"This displays!\");");
+    ASSERT_STREQ(lines[12].GetCStr(), "");
+    ASSERT_STREQ(lines[13].GetCStr(), "");
+    ASSERT_STREQ(lines[14].GetCStr(), "");
+    ASSERT_STREQ(lines[15].GetCStr(), "");
+    ASSERT_STREQ(lines[16].GetCStr(), "");
+    ASSERT_STREQ(lines[17].GetCStr(), "Display(\"This displays!\");");
+    ASSERT_STREQ(lines[18].GetCStr(), "");
+    ASSERT_STREQ(lines[19].GetCStr(), "");
+    ASSERT_STREQ(lines[20].GetCStr(), "Display(\"This displays!\");");
+    ASSERT_STREQ(lines[21].GetCStr(), "");
+    ASSERT_STREQ(lines[22].GetCStr(), "");
+    ASSERT_STREQ(lines[23].GetCStr(), "");
+}
+
+
 TEST(Preprocess, IfVer) {
     Preprocessor pp = Preprocessor();
     pp.SetAppVersion("3.6.0.5");
@@ -390,6 +452,21 @@ Display("test");
     EXPECT_STREQ(last_seen_cc_error(), "#endif has no matching #if");
 }
 
+TEST(Preprocess, ElseWithoutIf) {
+    Preprocessor pp = Preprocessor();
+    const char* inpl = R"EOS(
+#ifdef BAR
+#endif
+Display("test");
+#else
+)EOS";
+
+    clear_error();
+    String res = pp.Preprocess(inpl, "ElseWithoutIf");
+
+    EXPECT_STREQ(last_seen_cc_error(), "#else has no matching #if");
+}
+
 
 } // Preprocessor
 } // AGS
diff --git a/Editor/AGS.CScript.Compiler/Entities/ErrorCode.cs b/Editor/AGS.CScript.Compiler/Entities/ErrorCode.cs
@@ -15,6 +15,7 @@ public enum ErrorCode
 		UserDefinedError,
 		EndIfWithoutIf,
 		IfWithoutEndIf,
+		ElseWithoutIf,
 		InvalidVersionNumber,
 		UnexpectedToken = 100,
 		InvalidUseOfKeyword,

diff --git a/Editor/AGS.CScript.Compiler/Preprocessor.cs b/Editor/AGS.CScript.Compiler/Preprocessor.cs
@@ -239,6 +239,18 @@ private string PreProcessDirective(string line)
 			{
 				ProcessConditionalDirective(directive, line, _results);
 			}
+			else if (directive == "else")
+			{
+				if (_conditionalStatements.Count > 0)
+				{
+					// Negate previous condition
+					_conditionalStatements.Push(!_conditionalStatements.Pop());
+				}
+				else
+				{
+					RecordError(ErrorCode.ElseWithoutIf, "#else has no matching #if");
+				}
+			}
 			else if (directive == "endif")
 			{
 				if (_conditionalStatements.Count > 0)

diff --git a/Editor/AGS.Editor/AutoComplete.cs b/Editor/AGS.Editor/AutoComplete.cs
@@ -446,6 +446,20 @@ private static void ProcessPreProcessorDirective(List<ScriptDefine> defines, ref
                     state.InsideIfDefBlock = macroName;
                 }
             }
+            else if (preProcessorDirective == "else")
+            {
+                // Negate previous condition
+                if (state.InsideIfDefBlock != null)
+                {
+                    state.InsideIfNDefBlock = state.InsideIfDefBlock;
+                    state.InsideIfDefBlock = null;
+                }
+                else if (state.InsideIfNDefBlock != null)
+                {
+                    state.InsideIfDefBlock = state.InsideIfNDefBlock;
+                    state.InsideIfNDefBlock = null;
+                }
+            }
             else if (preProcessorDirective == "endif")
             {
                 state.InsideIfNDefBlock = null;