add support for continue statement (#112)

InfiniteRain · lolleko · commit 7f39d57f6aeb · 2018-06-07T11:48:45.000+02:00
* add support for continue statement

* make us of lua goto; decrease code reusage; add tests

* implement requested changes

* add continue translation tests; minor requested changes

* fix tupleArrayUses translation test
diff --git a/src/Transpiler.ts b/src/Transpiler.ts
@@ -61,6 +61,7 @@ export class LuaTranspiler {
     public importCount: number;
     public isModule: boolean;
     public sourceFile: ts.SourceFile;
+    public loopStack: number[];
 
     constructor(checker: ts.TypeChecker, options: ts.CompilerOptions, sourceFile: ts.SourceFile) {
         this.indent = "";
@@ -72,6 +73,7 @@ export class LuaTranspiler {
         this.importCount = 0;
         this.sourceFile = sourceFile;
         this.isModule = tsHelper.isFileModule(sourceFile);
+        this.loopStack = [];
     }
 
     public pushIndent(): void {
@@ -194,8 +196,7 @@ export class LuaTranspiler {
             case ts.SyntaxKind.ThrowStatement:
                 return this.transpileThrow(node as ts.ThrowStatement);
             case ts.SyntaxKind.ContinueStatement:
-                // Disallow continue
-                throw new TranspileError("Continue is not supported in Lua", node);
+                return this.transpileContinue();
             case ts.SyntaxKind.TypeAliasDeclaration:
             case ts.SyntaxKind.InterfaceDeclaration:
             case ts.SyntaxKind.EndOfFileToken:
@@ -317,6 +318,10 @@ export class LuaTranspiler {
         }
     }
 
+    public transpileContinue(): string {
+        return this.indent + `goto __continue${this.loopStack[this.loopStack.length - 1]}\n`;
+    }
+
     public transpileIf(node: ts.IfStatement): string {
         const condition = this.transpileExpression(node.expression);
 
@@ -335,12 +340,30 @@ export class LuaTranspiler {
         return result + this.indent + "end\n";
     }
 
+    public transpileLoopBody(
+        node: ts.WhileStatement
+            | ts.DoStatement
+            | ts.ForStatement
+            | ts.ForOfStatement
+            | ts.ForInStatement
+    ): string {
+        this.loopStack.push(this.genVarCounter);
+        this.genVarCounter++;
+        let result = this.indent + "do\n";
+        this.pushIndent();
+        result += this.transpileStatement(node.statement);
+        this.popIndent();
+        result += this.indent + "end\n";
+        result += this.indent + `::__continue${this.loopStack.pop()}::\n`;
+        return result;
+    }
+
     public transpileWhile(node: ts.WhileStatement): string {
         const condition = this.transpileExpression(node.expression);
 
         let result = this.indent + `while ${condition} do\n`;
         this.pushIndent();
-        result += this.transpileStatement(node.statement);
+        result += this.transpileLoopBody(node);
         this.popIndent();
         return result + this.indent + "end\n";
     }
@@ -349,7 +372,7 @@ export class LuaTranspiler {
         let result = this.indent + `repeat\n`;
 
         this.pushIndent();
-        result += this.transpileStatement(node.statement);
+        result += this.transpileLoopBody(node);
         this.popIndent();
 
         // Negate the expression because we translate from do-while to repeat-until (repeat-while-not)
@@ -368,7 +391,7 @@ export class LuaTranspiler {
 
         // Add body
         this.pushIndent();
-        result += this.transpileStatement(node.statement);
+        result += this.transpileLoopBody(node);
         result += this.indent + this.transpileExpression(node.incrementor) + "\n";
         this.popIndent();
 
@@ -394,7 +417,7 @@ export class LuaTranspiler {
 
         // For body
         this.pushIndent();
-        result += this.transpileStatement(node.statement);
+        result += this.transpileLoopBody(node);
         this.popIndent();
 
         return result + this.indent + "end\n";
@@ -417,7 +440,7 @@ export class LuaTranspiler {
 
         // For body
         this.pushIndent();
-        result += this.transpileStatement(node.statement);
+        result += this.transpileLoopBody(node);
         this.popIndent();
 
         return result + this.indent + "end\n";
diff --git a/test/translation/lua/continue.lua b/test/translation/lua/continue.lua
@@ -0,0 +1,10 @@
+local i = 0
+while(i<10) do
+    do
+        if i<5 then
+            goto __continue0
+        end
+    end
+    ::__continue0::
+    i=i+1
+end
diff --git a/test/translation/lua/continueConcurrent.lua b/test/translation/lua/continueConcurrent.lua
@@ -0,0 +1,13 @@
+local i = 0
+while(i<10) do
+    do
+        if i<5 then
+            goto __continue0
+        end
+        if i==7 then
+            goto __continue0
+        end
+    end
+    ::__continue0::
+    i=i+1
+end
diff --git a/test/translation/lua/continueNested.lua b/test/translation/lua/continueNested.lua
@@ -0,0 +1,20 @@
+local i = 0
+while(i<5) do
+    do
+        if (i%2)==0 then
+            goto __continue0
+        end
+        local j = 0
+        while(j<2) do
+            do
+                if j==1 then
+                    goto __continue1
+                end
+            end
+            ::__continue1::
+            j=j+1
+        end
+    end
+    ::__continue0::
+    i=i+1
+end
diff --git a/test/translation/lua/continueNestedConcurrent.lua b/test/translation/lua/continueNestedConcurrent.lua
@@ -0,0 +1,23 @@
+local i = 0
+while(i<5) do
+    do
+        if (i%2)==0 then
+            goto __continue0
+        end
+        local j = 0
+        while(j<2) do
+            do
+                if j==1 then
+                    goto __continue1
+                end
+            end
+            ::__continue1::
+            j=j+1
+        end
+        if i==4 then
+            goto __continue0
+        end
+    end
+    ::__continue0::
+    i=i+1
+end
diff --git a/test/translation/lua/do.lua b/test/translation/lua/do.lua
@@ -0,0 +1,8 @@
+local e = 10
+
+repeat
+    do
+        e=e-1
+    end
+    ::__continue0::
+until not (e>0)
diff --git a/test/translation/lua/for.lua b/test/translation/lua/for.lua
@@ -0,0 +1,7 @@
+local i = 1
+while(i<=100) do
+    do
+    end
+    ::__continue0::
+    i=i+1
+end
diff --git a/test/translation/lua/forIn.lua b/test/translation/lua/forIn.lua
@@ -0,0 +1,5 @@
+for i, _ in pairs({a = 1,b = 2,c = 3,d = 4}) do
+    do
+    end
+    ::__continue0::
+end
diff --git a/test/translation/lua/forOf.lua b/test/translation/lua/forOf.lua
@@ -0,0 +1,5 @@
+for _, i in ipairs({1,2,3,4,5,6,7,8,9,10}) do
+    do
+    end
+    ::__continue0::
+end
diff --git a/test/translation/lua/tupleArrayUses.lua b/test/translation/lua/tupleArrayUses.lua
@@ -1,4 +1,7 @@
 for _, value in ipairs(tuple) do
+    do
+    end
+    ::__continue0::
 end
 TS_forEach(tuple, function(v)
 end
diff --git a/test/translation/lua/while.lua b/test/translation/lua/while.lua
@@ -0,0 +1,8 @@
+local d = 10
+
+while d>0 do
+    do
+        d=d-1
+    end
+    ::__continue0::
+end
diff --git a/test/translation/ts/continue.ts b/test/translation/ts/continue.ts
@@ -0,0 +1,5 @@
+for (let i = 0; i < 10; i++) {
+    if (i < 5) {
+        continue;
+    }
+}
diff --git a/test/translation/ts/continueConcurrent.ts b/test/translation/ts/continueConcurrent.ts
@@ -0,0 +1,9 @@
+for (let i = 0; i < 10; i++) {
+    if (i < 5) {
+        continue;
+    }
+
+    if (i === 7) {
+        continue;
+    }
+}
diff --git a/test/translation/ts/continueNested.ts b/test/translation/ts/continueNested.ts
@@ -0,0 +1,11 @@
+for (let i = 0; i < 5; i++) {
+    if (i % 2 === 0) {
+        continue;
+    }
+
+    for (let j = 0; j < 2; j++) {
+        if (j === 1) {
+            continue;
+        }
+    }
+}
diff --git a/test/translation/ts/continueNestedConcurrent.ts b/test/translation/ts/continueNestedConcurrent.ts
@@ -0,0 +1,15 @@
+for (let i = 0; i < 5; i++) {
+    if (i % 2 === 0) {
+        continue;
+    }
+
+    for (let j = 0; j < 2; j++) {
+        if (j === 1) {
+            continue;
+        }
+    }
+
+    if (i === 4) {
+        continue;
+    }
+}
diff --git a/test/translation/ts/do.ts b/test/translation/ts/do.ts
@@ -0,0 +1,4 @@
+let e = 10
+do {
+  e--;
+} while (e > 0)
diff --git a/test/translation/ts/for.ts b/test/translation/ts/for.ts
@@ -0,0 +1,2 @@
+for (let i = 1; i <= 100; i++) {
+}
diff --git a/test/translation/ts/forIn.ts b/test/translation/ts/forIn.ts
@@ -0,0 +1,7 @@
+for (let i in {
+  a: 1,
+  b: 2,
+  c: 3,
+  d: 4
+}) {
+}
diff --git a/test/translation/ts/forOf.ts b/test/translation/ts/forOf.ts
@@ -0,0 +1,2 @@
+for (let i of [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]) {
+}
diff --git a/test/translation/ts/while.ts b/test/translation/ts/while.ts
@@ -0,0 +1,4 @@
+let d = 10;
+while (d > 0) {
+  d--;
+}
diff --git a/test/unit/loops.spec.ts b/test/unit/loops.spec.ts
diff --git a/test/unit/while.spec.ts b/test/unit/while.spec.ts

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +for i, _ in pairs({a = 1,b = 2,c = 3,d = 4}) do
 +    do
 +    end
 +    ::__continue0::
 +end