fix bool/string literals; add tests

Author: mmoskal

compiler/src/compiler.ts

@@ -862,13 +862,22 @@ class Program implements TopOpWriter {
         }
     }
 
+    private valueIsAlwaysFalse(v: Value) {
+        if (v.isLiteral) return v.numValue == 0
+        return v.op == Op.EXPR0_FALSE || v.op == Op.EXPR0_NULL
+    }
+
+    private valueIsAlwaysTrue(v: Value) {
+        if (v.isLiteral) return v.numValue != 0 && !isNaN(v.numValue)
+        return v.op == Op.EXPR0_TRUE
+    }
+
     private emitIfStatement(stmt: ts.IfStatement) {
         const cond = this.emitSimpleValue(stmt.expression, ValueType.BOOL)
-        if (cond.isLiteral) {
-            if (cond.numValue) this.emitStmt(stmt.thenStatement)
-            else {
-                if (stmt.elseStatement) this.emitStmt(stmt.elseStatement)
-            }
+        if (this.valueIsAlwaysFalse(cond)) {
+            if (stmt.elseStatement) this.emitStmt(stmt.elseStatement)
+        } else if (this.valueIsAlwaysTrue(cond)) {
+            this.emitStmt(stmt.thenStatement)
         } else {
             this.writer.emitIfAndPop(
                 cond,
@@ -2489,15 +2498,16 @@ class Program implements TopOpWriter {
     }
 
     private emitLiteral(v: any, node?: ts.Node) {
-        if (v === true) v = 1
-        else if (v === false) v = 0
-
-        if (v === null || v === undefined) return literal(v)
+        if (
+            v === null ||
+            v === undefined ||
+            typeof v == "number" ||
+            typeof v == "boolean"
+        )
+            return literal(v)
 
         if (typeof v == "string") return this.writer.emitString(v)
 
-        if (typeof v == "number") return literal(v)
-
         throwError(node, "unhandled literal: " + v)
     }
 
@@ -2792,7 +2802,11 @@ class Program implements TopOpWriter {
         let a = this.emitSimpleValue(expr.left, dstTp)
         let b = this.emitSimpleValue(expr.right, dstTp)
         if (swap) [a, b] = [b, a]
-        return wr.emitExpr(op2, a, b)
+
+        const res = wr.emitExpr(op2, a, b)
+        if (op2 == Op.EXPR2_ADD && this.isStringLike(expr))
+            res.valueType = ValueType.STRING
+        return res
     }
 
     private emitUnaryExpression(expr: ts.PrefixUnaryExpression): Value {

compiler/src/opwriter.ts

@@ -122,13 +122,19 @@ export class CachedValue {
     }
 }
 
-export function literal(v: number) {
+export function literal(v: number | boolean) {
     if (v == null) {
         const r = new Value(ValueType.NULL)
         r.op = Op.EXPR0_NULL
         r.args = []
         r.flags = 0
         return r
+    } else if (typeof v == "boolean") {
+        const r = new Value(ValueType.BOOL)
+        r.op = v ? Op.EXPR0_TRUE : Op.EXPR0_FALSE
+        r.args = []
+        r.flags = 0
+        return r
     } else {
         const r = new Value(ValueType.NUMBER)
         r.numValue = v
@@ -275,7 +281,9 @@ export class OpWriter {
     }
 
     emitString(s: string | Uint8Array) {
-        const v = new Value(ValueType.BUFFER)
+        const v = new Value(
+            typeof s == "string" ? ValueType.STRING : ValueType.BUFFER
+        )
         let idx = 0
         if (typeof s == "string") {
             idx = this.prog.addString(s)

devs/run-tests/basic.ts

@@ -17,6 +17,13 @@ function isEq(x: number, y: number): void {
     }
 }
 
+function strEq(a: string, b: string) {
+    if (a != b) {
+        console.log(`fail: '${a}' != '${b}'`)
+        panic(110)
+    }
+}
+
 let x = 0
 
 function testFlow() {
@@ -245,6 +252,26 @@ function testConsole() {
     console.log(`text ${n} + ${q} is`, n + q)
 }
 
+function testString() {
+    strEq("a" + "b", "ab")
+    strEq("a" + 1, "a1")
+    strEq(1 + "a", "1a")
+    strEq(":" + true, ":true")
+    strEq(":" + false, ":false")
+    strEq(":" + null, ":null")
+    strEq(":" + 1.4, ":1.4")
+    strEq(":" + NaN, ":NaN")
+
+    const b = Buffer.alloc(3)
+    b[0] = 0x42
+    b[1] = 0x6c
+    strEq(":" + b, ":[Buffer[3] 426c00]")
+
+    strEq(`x${1}`, "x1")
+    strEq(`x${true}x`, "xtruex")
+    strEq(`x ${null} x`, "x null x")
+}
+
 testFlow()
 if (x != 42) panic(10)
 testMath()
@@ -253,5 +280,6 @@ testBuffer()
 testArray()
 testObj()
 testConsole()
+testString()
 console.log("all OK")
 ds.reboot()