From e2b8c069d7e386e40b187e7351601b9c0374a391 Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Mon, 24 Jan 2022 23:30:15 +0100
Subject: [PATCH] check for missing '&' in string + value expressions (can't
 just add a value to a string)

---
 .../compiler/astprocessing/AstChecker.kt      |  7 +++
 compiler/test/TestAstChecks.kt                | 41 ++++++++++++++++
 docs/source/todo.rst                          |  2 -
 examples/test.p8                              | 48 +++++--------------
 4 files changed, 60 insertions(+), 38 deletions(-)

diff --git a/compiler/src/prog8/compiler/astprocessing/AstChecker.kt b/compiler/src/prog8/compiler/astprocessing/AstChecker.kt
index 2db3c8c0d..a06a387f8 100644
--- a/compiler/src/prog8/compiler/astprocessing/AstChecker.kt
+++ b/compiler/src/prog8/compiler/astprocessing/AstChecker.kt
@@ -835,6 +835,13 @@ internal class AstChecker(private val program: Program,
         val leftDt = leftIDt.getOr(DataType.UNDEFINED)
         val rightDt = rightIDt.getOr(DataType.UNDEFINED)
 
+        if(expr.operator=="+" || expr.operator=="-") {
+            if(leftDt == DataType.STR || rightDt == DataType.STR || leftDt in ArrayDatatypes || rightDt in ArrayDatatypes) {
+                errors.err("missing & (address-of) on the string operand", expr.position)
+                return
+            }
+        }
+
         when(expr.operator){
             "/", "%" -> {
                 val constvalRight = expr.right.constValue(program)
diff --git a/compiler/test/TestAstChecks.kt b/compiler/test/TestAstChecks.kt
index 8c8e9532f..18a0fc2df 100644
--- a/compiler/test/TestAstChecks.kt
+++ b/compiler/test/TestAstChecks.kt
@@ -56,4 +56,45 @@ class TestAstChecks: FunSpec({
         errors.errors[0] shouldContain ":7:28) assignment value is invalid"
         errors.errors[1] shouldContain ":8:28) assignment value is invalid"
     }
+
+    test("can't do str or array expression without using address-of") {
+        val text = """
+            %import textio
+            main {
+                sub start() {
+                    ubyte[] array = [1,2,3,4]
+                    str s1 = "test"
+                    ubyte ff = 1
+                    txt.print(s1+ff)
+                    txt.print(array+ff)
+                    txt.print_uwhex(s1+ff, true)
+                    txt.print_uwhex(array+ff, true)
+                }
+            }
+            """
+        val errors = ErrorReporterForTests()
+        compileText(C64Target, false, text, writeAssembly = false, errors=errors).assertFailure()
+        errors.errors.filter { it.contains("missing &") }.size shouldBe 4
+    }
+
+    test("str or array expression with address-of") {
+        val text = """
+            %import textio
+            main {
+                sub start() {
+                    ubyte[] array = [1,2,3,4]
+                    str s1 = "test"
+                    ubyte ff = 1
+                    txt.print(&s1+ff)
+                    txt.print(&array+ff)
+                    txt.print_uwhex(&s1+ff, true)
+                    txt.print_uwhex(&array+ff, true)
+                    ; also good:
+                    ff = (s1 == "derp")
+                    ff = (s1 != "derp")
+                }
+            }
+            """
+        compileText(C64Target, false, text, writeAssembly = false).assertSuccess()
+    }
 })
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index 5dd9f622e..56b51c94c 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -3,8 +3,6 @@ TODO
 
 For next release
 ^^^^^^^^^^^^^^^^
-- str s1, ubyte ff,  txt.print_uwhex(s1+ff, true)        ; TODO fix compiler crash on s1+ff.   why no crash when using 1-argument functioncall?
-
 ...
 
 
diff --git a/examples/test.p8 b/examples/test.p8
index dfb219df5..b781b0192 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -4,43 +4,19 @@
 
 main {
     sub start() {
-        str s1 = "irmen@razorvine.net"
+        str s1 = "irmen"
+        ubyte ff = 1
+        txt.print(&s1+ff)
+        txt.nl()
+        txt.print(&s1+ff)
+        txt.nl()
+        txt.print_uwhex(&s1+ff, true)
 
-        ubyte qq = '@'
 
-        if qq in s1
-            txt.print("good1\n")
-        else
-            txt.print("error1\n")
-
-        if 'r' in s1
-            txt.print("good2\n")
-        else
-            txt.print("error2\n")
-
-        if qq in "irmen22@razorvine.netirmen22@razorvine.netirmen22@razorvine.netirmen22@razorvine.net"
-            txt.print("good3\n")
-        else
-            txt.print("error3\n")
-
-        qq = 2
-        if qq in [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2]
-            txt.print("good4\n")
-        else
-            txt.print("error4\n")
-
-        qq='z'
-        if qq in "irm@razo"
-            txt.print("good5\n")
-        else
-            txt.print("error5\n")
-
-        uword zz = 2222
-        if zz in [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2222,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2]
-            txt.print("good6\n")
-        else
-            txt.print("error6\n")
-
-        ; str s1, ubyte ff,  txt.print_uwhex(s1+ff, true)        ; TODO fix compiler crash on s1+ff.   why no crash when using 1-argument functioncall?
+        ubyte[] array = [1,2,3,4]
+        txt.print_uwhex(&array+ff, true)
+        txt.nl()
+        txt.print_uwhex(&array+ff, true)
+        txt.nl()
     }
 }