Add CheckReturnValue annotation

2 files changed, 65 insertions, 0 deletions

diff --git a/src/main/java/org/shedlang/compiler/patio/PatioCodeGenContext.java b/src/main/java/org/shedlang/compiler/patio/PatioCodeGenContext.java
index fd45f29d..da417cf5 100644
--- a/src/main/java/org/shedlang/compiler/patio/PatioCodeGenContext.java
+++ b/src/main/java/org/shedlang/compiler/patio/PatioCodeGenContext.java
@@ -14,6 +14,7 @@ import org.shedlang.compiler.patio.ast.types.PatioType;
 import org.shedlang.compiler.sources.Source;
 import org.shedlang.compiler.typechecker.TypeInfos;
 import org.shedlang.compiler.types.*;
+import org.shedlang.compiler.util.CheckReturnValue;
 import org.shedlang.compiler.util.P;
 
 import java.util.ArrayList;
@@ -35,6 +36,7 @@ public record PatioCodeGenContext(
     ) {
         public static final GlobalContext EMPTY = forTypeInfos(TypeInfos.EMPTY);
 
+        @CheckReturnValue
         public static GlobalContext forTypeInfos(TypeInfos typeInfos) {
             var structTags = generateStructTags(typeInfos);
             var effectTags = generateEffectTags(typeInfos);
@@ -46,6 +48,7 @@ public record PatioCodeGenContext(
             );
         }
 
+        @CheckReturnValue
         private static PMap<StructType, Integer> generateStructTags(TypeInfos typeInfos) {
             var tags = P.<StructType, Integer>map();
             var nextTag = 0;
@@ -56,6 +59,7 @@ public record PatioCodeGenContext(
             return tags;
         }
 
+        @CheckReturnValue
         private static PMap<UserDefinedEffect, Integer> generateEffectTags(TypeInfos typeInfos) {
             var tags = P.<UserDefinedEffect, Integer>map();
             var nextTag = 0;
@@ -66,18 +70,21 @@ public record PatioCodeGenContext(
             return tags;
         }
 
+        @CheckReturnValue
         public NamespaceTypeInfo namespaceTypeInfo(NamespaceName namespaceName) {
             return typeInfos.namespaceTypeInfo(namespaceName)
                 // TODO: throw better error
                 .orElseThrow(() -> new RuntimeException("No type info for: " + namespaceName));
         }
 
+        @CheckReturnValue
         public StructTypeInfo structTypeInfo(StructType type) {
             return typeInfos.structTypeInfo(type)
                 // TODO: throw better error
                 .orElseThrow(() -> new RuntimeException("No type info for: " + type));
         }
 
+        @CheckReturnValue
         public int structTag(StructType type) {
             var tag = this.structTags.get(type);
             if (tag == null) {
@@ -88,12 +95,14 @@ public record PatioCodeGenContext(
             }
         }
 
+        @CheckReturnValue
         public UserDefinedEffectInfo userDefinedEffectInfo(UserDefinedEffect effect) {
             return typeInfos.userDefinedEffectInfo(effect)
                 // TODO: throw better error
                 .orElseThrow(() -> new RuntimeException("No effect info for: " + effect));
         }
 
+        @CheckReturnValue
         public int effectTag(UserDefinedEffect effect) {
             var tag = this.effectTags.get(effect);
             if (tag == null) {
@@ -110,6 +119,7 @@ public record PatioCodeGenContext(
     ) {
         public static CompilationUnitContext EMPTY = new CompilationUnitContext(OrderedPMap.empty());
 
+        @CheckReturnValue
         public CompilationUnitContext addElement(PatioCompilationUnitElement element) {
             // TODO: handle existing element with name.
             return new CompilationUnitContext(
@@ -117,10 +127,12 @@ public record PatioCodeGenContext(
             );
         }
 
+        @CheckReturnValue
         private <T> Result<T> toResult(T value) {
             return new Result<>(value, this);
         }
 
+        @CheckReturnValue
         public Result<String> allocateCompilationUnitName(
             PatioCodeGenCompilationUnitElementSpace space,
             Optional<String> name
@@ -134,6 +146,7 @@ public record PatioCodeGenContext(
             return toResult(fullName);
         }
 
+        @CheckReturnValue
         public CompilationUnitContext addCompilationUnitElement(
             PatioCompilationUnitElement element
         ) {
@@ -160,6 +173,7 @@ public record PatioCodeGenContext(
             P.map()
         );
 
+        @CheckReturnValue
         public Result<PatioLocalRef> temporaryPop() {
             return new FunctionContext(
                 this.temporaryStack.minus(0),
@@ -170,6 +184,7 @@ public record PatioCodeGenContext(
             ).toResult(this.temporaryStack.get(0));
         }
 
+        @CheckReturnValue
         public FunctionContext temporaryPush(PatioLocalRef value) {
             return new FunctionContext(
                 this.temporaryStack.plus(value),
@@ -180,6 +195,7 @@ public record PatioCodeGenContext(
             );
         }
 
+        @CheckReturnValue
         public FunctionContext addInstruction(PatioInstruction instruction) {
             return new FunctionContext(
                 this.temporaryStack,
@@ -190,6 +206,7 @@ public record PatioCodeGenContext(
             );
         }
 
+        @CheckReturnValue
         public Result<PatioLocalRef> allocateLocal(
             PatioCodeGenLocalSpace space,
             Optional<String> name,
@@ -211,6 +228,7 @@ public record PatioCodeGenContext(
             ).toResult(new PatioLocalRef(fullName));
         }
 
+        @CheckReturnValue
         public Result<PVector<Function<PatioCodeGenContext, PatioCodeGenContext>>> addStackIrLocal(
             String name,
             PatioLocalFactory createLocal
@@ -245,6 +263,7 @@ public record PatioCodeGenContext(
             return context.toResult(this.waitingForStackIrLocal.getOrDefault(name, P.vector()));
         }
 
+        @CheckReturnValue
         public PatioLocalRef stackIrLocalNameToLocal(String name) {
             var local = this.stackIrNameToLocal.get(name);
 
@@ -256,12 +275,14 @@ public record PatioCodeGenContext(
             return local;
         }
 
+        @CheckReturnValue
         public Optional<PatioLocalRef> stackIrLocalNameToLocalOrNone(String name) {
             var local = this.stackIrNameToLocal.get(name);
 
             return Optional.ofNullable(local);
         }
 
+        @CheckReturnValue
         public FunctionContext addWaitingForShedLocal(
             String name,
             Function<PatioCodeGenContext, PatioCodeGenContext> func
@@ -292,6 +313,7 @@ public record PatioCodeGenContext(
         FunctionContext.EMPTY
     );
 
+    @CheckReturnValue
     public static PatioCodeGenContext forTypeInfos(TypeInfos typeInfos) {
         return new PatioCodeGenContext(
             GlobalContext.forTypeInfos(typeInfos),
@@ -301,26 +323,32 @@ public record PatioCodeGenContext(
         );
     }
 
+    @CheckReturnValue
     public NamespaceTypeInfo namespaceTypeInfo(NamespaceName namespaceName) {
         return this.globalContext.namespaceTypeInfo(namespaceName);
     }
 
+    @CheckReturnValue
     public StructTypeInfo structTypeInfo(StructType type) {
         return this.globalContext.structTypeInfo(type);
     }
 
+    @CheckReturnValue
     public int structTag(StructType type) {
         return globalContext.structTag(type);
     }
 
+    @CheckReturnValue
     public UserDefinedEffectInfo userDefinedEffectInfo(UserDefinedEffect effect) {
         return this.globalContext.userDefinedEffectInfo(effect);
     }
 
+    @CheckReturnValue
     public int effectTag(UserDefinedEffect effect) {
         return globalContext.effectTag(effect);
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<String> allocateCompilationUnitElementName(
         PatioCodeGenCompilationUnitElementSpace space,
         String name
@@ -333,6 +361,7 @@ public record PatioCodeGenContext(
         );
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<String> allocateCompilationUnitElementName(
         PatioCodeGenCompilationUnitElementSpace space
     ) {
@@ -344,11 +373,13 @@ public record PatioCodeGenContext(
         );
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext addDataElementMutable(String name, PatioDataLayout layout, Source source) {
         var dataElement = new PatioDataElementMutable(name, layout, source);
         return addCompilationUnitElement(dataElement);
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext addCompilationUnitElement(
         PatioCompilationUnitElement element
     ) {
@@ -357,12 +388,14 @@ public record PatioCodeGenContext(
         );
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<PatioLocalRef> temporaryPop() {
         var result = this.functionContext.temporaryPop();
 
         return withFunctionContextResult(result);
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext temporaryPopIntoLocal(PatioLocalRef target, Source source) {
         var result = this.functionContext.temporaryPop();
 
@@ -370,16 +403,19 @@ public record PatioCodeGenContext(
             .addInstruction(new PatioLocalStore(target, result.value, source));
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext temporaryPush(PatioLocalRef value) {
         var result = this.functionContext.temporaryPush(value);
 
         return withFunctionContext(result);
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext addInstruction(PatioInstruction instruction) {
         return withFunctionContext(this.functionContext.addInstruction(instruction));
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<PatioLocalRef> allocateParam(
         PatioCodeGenLocalSpace space,
         PatioType type
@@ -394,6 +430,7 @@ public record PatioCodeGenContext(
         return withFunctionContextResult(result);
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<PatioLocalRef> allocateParam(
         PatioCodeGenLocalSpace space,
         String name,
@@ -409,6 +446,7 @@ public record PatioCodeGenContext(
         return withFunctionContextResult(result);
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<PatioLocalRef> allocateVal(
         PatioCodeGenLocalSpace space,
         PatioType type
@@ -423,6 +461,7 @@ public record PatioCodeGenContext(
         return withFunctionContextResult(result);
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<PatioLocalRef> allocateVal(
         PatioCodeGenLocalSpace space,
         String name,
@@ -438,12 +477,14 @@ public record PatioCodeGenContext(
         return withFunctionContextResult(result);
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext addStackIrParam(
         String name
     ) {
         return addStackIrLocal(name, (l, c) -> c, PatioLocal.Param::new);
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext addStackIrVal(
         String name,
         BiFunction<PatioLocalRef, PatioCodeGenContext, PatioCodeGenContext> setLocal
@@ -451,6 +492,7 @@ public record PatioCodeGenContext(
         return addStackIrLocal(name, setLocal, PatioLocal.Val::new);
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext addStackIrVarIfMissing(
         String name
     ) {
@@ -462,6 +504,7 @@ public record PatioCodeGenContext(
         }
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext addStackIrLocal(
         String name,
         BiFunction<PatioLocalRef, PatioCodeGenContext, PatioCodeGenContext> setLocal,
@@ -481,6 +524,7 @@ public record PatioCodeGenContext(
         return context;
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext onceStackIrLocalDefined(
         String name,
         Function<PatioCodeGenContext, PatioCodeGenContext> func
@@ -496,10 +540,12 @@ public record PatioCodeGenContext(
         }
     }
 
+    @CheckReturnValue
     public PatioLocalRef stackIrLocalNameToLocal(String name) {
         return this.functionContext.stackIrLocalNameToLocal(name);
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext createFunction(
         String name,
         PatioVisibility visibility,
@@ -533,6 +579,7 @@ public record PatioCodeGenContext(
         );
     }
 
+    @CheckReturnValue
     public PatioCodeGenContext enterBlock() {
         return new PatioCodeGenContext(
             this.globalContext,
@@ -548,6 +595,7 @@ public record PatioCodeGenContext(
         );
     }
 
+    @CheckReturnValue
     public PatioCodeGenResult<List<PatioInstruction>> exitBlock() {
         if (!this.functionContext.temporaryStack.isEmpty()) {
             throw new RuntimeException("temporary stack must be empty at the end of a block");
@@ -567,26 +615,32 @@ public record PatioCodeGenContext(
         ).toResult(this.functionContext.instructions);
     }
 
+    @CheckReturnValue
     private PatioCodeGenContext withCompilationUnitContext(CompilationUnitContext compilationUnitContext) {
         return new PatioCodeGenContext(this.globalContext, compilationUnitContext, this.blockStack, this.functionContext);
     }
 
+    @CheckReturnValue
     private <T> PatioCodeGenResult<T> withCompilationUnitContextResult(CompilationUnitContext.Result<T> result) {
         return withCompilationUnitContext(result.context).toResult(result.value);
     }
 
+    @CheckReturnValue
     private PatioCodeGenContext withFunctionContext(FunctionContext functionContext) {
         return new PatioCodeGenContext(this.globalContext, this.compilationUnitContext, this.blockStack, functionContext);
     }
 
+    @CheckReturnValue
     private <T> PatioCodeGenResult<T> withFunctionContextResult(FunctionContext.Result<T> result) {
         return withFunctionContext(result.context).toResult(result.value);
     }
 
+    @CheckReturnValue
     public <T> PatioCodeGenResult<T> toResult(T value) {
         return new PatioCodeGenResult<>(value, this);
     }
 
+    @CheckReturnValue
     public PatioCompilationUnit toCompilationUnit(Source source) {
         return new PatioCompilationUnit(
             new ArrayList<>(this.compilationUnitContext.elementsByName.values()),
diff --git a/src/main/java/org/shedlang/compiler/util/CheckReturnValue.java b/src/main/java/org/shedlang/compiler/util/CheckReturnValue.java
new file mode 100644
index 00000000..2e5ad19a
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/util/CheckReturnValue.java
@@ -0,0 +1,11 @@
+package org.shedlang.compiler.util;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.SOURCE)
+public @interface CheckReturnValue {
+}