Allowing return from expression if (#1080)

Enhancements:
- Allow a return statement in final position in an if expression (see #1060)

Notes:
- Return from a statement if short-circuits the expression and returns from the enclosing function

.config/dotnet-tools.json

@@ -15,7 +15,7 @@
       ]
     },
     "ghul.compiler": {
-      "version": "0.7.10",
+      "version": "0.7.11",
       "commands": [
         "ghul-compiler"
       ]

integration-tests/execution/statement-expression-if-2/.vscode/tasks.json

@@ -0,0 +1,23 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "Run test",
+            "command": "dotnet ghul-test \"${workspaceFolder}\"",
+            "type": "shell",
+            "group": {
+                "kind": "test",
+                "isDefault": true
+            }
+        },
+        {
+            "label": "Capture test expectation",
+            "command": "../../../tasks/capture.sh \"${workspaceFolder}\"",
+            "type": "shell",
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            }
+        }
+    ]
+}

integration-tests/execution/statement-expression-if-2/ghul.json

@@ -0,0 +1,6 @@
+{
+    "compiler": "../../../publish/ghul.exe",
+    "source": [
+        "."
+    ]
+}

integration-tests/execution/statement-expression-if-2/run.expected

@@ -0,0 +1,45 @@
+test if 0: too small
+test elif 0: 0 is less than five
+test else 0: 0 is less than five
+test if 1: too small
+test elif 1: 1 is less than five
+test else 1: 1 is less than five
+test if 2: too small
+test elif 2: 2 is less than five
+test else 2: 2 is less than five
+test if 3: too small
+test elif 3: 3 is less than five
+test else 3: 3 is less than five
+test if 4: too small
+test elif 4: 4 is less than five
+test else 4: 4 is less than five
+test if 5: 5 is less than ten
+test elif 5: just right
+test else 5: 5 is less than ten
+test if 6: 6 is less than ten
+test elif 6: just right
+test else 6: 6 is less than ten
+test if 7: 7 is less than ten
+test elif 7: just right
+test else 7: 7 is less than ten
+test if 8: 8 is less than ten
+test elif 8: just right
+test else 8: 8 is less than ten
+test if 9: 9 is less than ten
+test elif 9: just right
+test else 9: 9 is less than ten
+test if 10: 10 is ten or more
+test elif 10: 10 is too big
+test else 10: too big
+test if 11: 11 is ten or more
+test elif 11: 11 is too big
+test else 11: too big
+test if 12: 12 is ten or more
+test elif 12: 12 is too big
+test else 12: too big
+test if 13: 13 is ten or more
+test elif 13: 13 is too big
+test else 13: too big
+test if 14: 14 is ten or more
+test elif 14: 14 is too big
+test else 14: too big

integration-tests/execution/statement-expression-if-2/test.ghul

@@ -0,0 +1,160 @@
+use IO.Std.write_line;
+
+entry() is
+    for i in 0..15 do
+        write_line("test if " + i + ": " + test_return_if(i));
+        write_line("test elif " + i + ": " + test_return_elif(i));
+        write_line("test else " + i + ": " + test_return_else(i));
+
+        // TODO these don't work yet
+        /*
+        test_break_if(i);
+        test_break_elif(i);
+        test_break_else(i);
+        test_continue_if(i);
+        test_continue_elif(i);
+        test_continue_else(i);
+        */
+    od
+si
+
+test_return_if(i: int) -> string is
+    let value = 
+        if i < 5 then
+            return "too small";
+        elif i < 10 then
+            "less than ten";
+        else
+            "ten or more";
+        fi;
+
+    return "" + i + " is " + value;
+si
+
+test_return_elif(i: int) -> string is
+    let value = 
+        if i < 5 then
+            "less than five";
+        elif i < 10 then
+            return "just right";
+        else
+            "too big";
+        fi;
+
+    return "" + i + " is " + value;
+si
+
+test_return_else(i: int) -> string is
+    let value = 
+        if i < 5 then
+            "less than five";
+        elif i < 10 then
+            "less than ten";
+        else
+            return "too big";
+        fi;
+
+    return "" + i + " is " + value;
+si
+
+/*
+test_break_if(limit: int) -> string is
+    let result = "";
+    for i in 0..10 do
+        result = result +
+            if i < limit then
+                "x" + i + " ";
+            else
+                break;
+            fi;
+
+        result = result + ".";
+    od
+
+    return result;
+si
+
+test_break_else(limit: int) -> string is
+    let result = "";
+    for i in 0..10 do
+        result = result +
+            if i > limit then
+                break;
+            else
+                "y" + i + " ";
+            fi;
+
+        result = result + ".";
+    od
+
+    return result;
+si
+
+test_break_elif(limit: int) -> string is
+    let result = "";
+    for i in 0..10 do
+        result = result +
+            if i < 3 then
+                "small";
+            elif i > limit then
+                break;
+            else
+                "z" + i;
+            fi;
+
+        result = result + ".";
+    od
+
+    return result;
+si
+
+test_continue_if(limit: int) -> string is
+    let result = "";
+    for i in 0..10 do
+        result = result +
+            if i < limit then
+                continue;
+            else
+                "x" + i + " ";
+            fi;
+
+        result = result + ".";
+    od
+
+    return result;
+si
+
+test_continue_else(limit: int) -> string is
+    let result = "";
+    for i in 0..10 do
+        result = result +
+            if i > limit then
+                "y" + i + " ";
+            else
+                continue;
+            fi;
+
+        result = result + ".";
+    od
+
+    return result;
+si
+
+test_continue_elif(limit: int) -> string is
+    let result = "";
+    for i in 0..10 do
+        result = result +
+            if i < 3 then
+                "small";
+            elif i > limit then
+                continue;
+            else
+                "z" + i;
+            fi;
+
+        result = result + ".";
+    od
+
+    return result;
+si
+*/

integration-tests/execution/statement-expression-if-3/.vscode/tasks.json

@@ -0,0 +1,23 @@
+{
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "Run test",
+            "command": "dotnet ghul-test \"${workspaceFolder}\"",
+            "type": "shell",
+            "group": {
+                "kind": "test",
+                "isDefault": true
+            }
+        },
+        {
+            "label": "Capture test expectation",
+            "command": "../../../tasks/capture.sh \"${workspaceFolder}\"",
+            "type": "shell",
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            }
+        }
+    ]
+}

integration-tests/execution/statement-expression-if-3/ghul.json

@@ -0,0 +1,6 @@
+{
+    "compiler": "../../../publish/ghul.exe",
+    "source": [
+        "."
+    ]
+}