fix: check for duplicate configs and secrets within a Go module (#1328)

Contributes to one part of
#1121

go-runtime/compile/schema.go

@@ -257,6 +257,23 @@ func parseConfigDecl(pctx *parseContext, node *ast.CallExpr, fn *types.Func) {
 			Type: st,
 		}
 	}
+
+	// Check for duplicates
+	for _, d := range pctx.module.Decls {
+		c, ok := d.(*schema.Config)
+		if ok && c.Name == name && c.Type.String() == st.String() {
+			_, endCol := goNodePosToSchemaPos(node)
+			pctx.errors.add(errorf(node, "duplicate config declaration at %d:%d-%d", c.Pos.Line, c.Pos.Column, endCol))
+			return
+		}
+		s, ok := d.(*schema.Secret)
+		if ok && s.Name == name && s.Type.String() == st.String() {
+			_, endCol := goNodePosToSchemaPos(node)
+			pctx.errors.add(errorf(node, "duplicate secret declaration at %d:%d-%d", s.Pos.Line, s.Pos.Column, endCol))
+			return
+		}
+	}
+
 	pctx.module.Decls = append(pctx.module.Decls, decl)
 }
 

go-runtime/compile/schema_test.go

@@ -247,35 +247,37 @@ func TestErrorReporting(t *testing.T) {
 	filename := filepath.Join(pwd, `testdata/failing/failing.go`)
 	assert.EqualError(t, errors.Join(genericizeErrors(schemaErrs)...),
 		filename+":10:13-35: config and secret declarations must have a single string literal argument\n"+
-			filename+":13:2-10: unsupported type \"error\" for field \"BadParam\"\n"+
-			filename+":16:2-17: unsupported type \"uint64\" for field \"AnotherBadParam\"\n"+
-			filename+":19:3-3: unexpected token \"verb\" (expected Directive)\n"+
-			filename+":25:36-39: unsupported request type \"ftl/failing.Request\"\n"+
-			filename+":25:50-50: unsupported response type \"ftl/failing.Response\"\n"+
-			filename+":26:16-29: call first argument must be a function in an ftl module\n"+
-			filename+":27:2-46: call must have exactly three arguments\n"+
-			filename+":28:16-25: call first argument must be a function\n"+
-			filename+":33:1-2: must have at most two parameters (context.Context, struct)\n"+
-			filename+":33:69-69: unsupported response type \"ftl/failing.Response\"\n"+
-			filename+":38:22-27: first parameter must be of type context.Context but is ftl/failing.Request\n"+
-			filename+":38:37-43: second parameter must be a struct but is string\n"+
-			filename+":38:53-53: unsupported response type \"ftl/failing.Response\"\n"+
-			filename+":43:43-47: second parameter must not be ftl.Unit\n"+
-			filename+":43:59-59: unsupported response type \"ftl/failing.Response\"\n"+
-			filename+":48:1-2: first parameter must be context.Context\n"+
-			filename+":48:18-18: unsupported response type \"ftl/failing.Response\"\n"+
-			filename+":53:1-2: must have at most two results (struct, error)\n"+
-			filename+":53:41-44: unsupported request type \"ftl/failing.Request\"\n"+
-			filename+":58:1-2: must at least return an error\n"+
-			filename+":58:36-39: unsupported request type \"ftl/failing.Request\"\n"+
-			filename+":62:35-38: unsupported request type \"ftl/failing.Request\"\n"+
-			filename+":62:48-48: must return an error but is ftl/failing.Response\n"+
-			filename+":67:41-44: unsupported request type \"ftl/failing.Request\"\n"+
-			filename+":67:55-55: first result must be a struct but is string\n"+
-			filename+":67:63-63: must return an error but is string\n"+
-			filename+":67:63-63: second result must not be ftl.Unit\n"+
-			filename+":74:1-1: verb \"WrongResponse\" already exported\n"+
-			filename+":80:2-12: struct field unexported must be exported by starting with an uppercase letter",
+			filename+":13:18-52: duplicate config declaration at 12:18-52\n"+
+			filename+":16:18-49: duplicate secret declaration at 15:18-49\n"+
+			filename+":19:2-10: unsupported type \"error\" for field \"BadParam\"\n"+
+			filename+":22:2-17: unsupported type \"uint64\" for field \"AnotherBadParam\"\n"+
+			filename+":25:3-3: unexpected token \"verb\" (expected Directive)\n"+
+			filename+":31:36-39: unsupported request type \"ftl/failing.Request\"\n"+
+			filename+":31:50-50: unsupported response type \"ftl/failing.Response\"\n"+
+			filename+":32:16-29: call first argument must be a function in an ftl module\n"+
+			filename+":33:2-46: call must have exactly three arguments\n"+
+			filename+":34:16-25: call first argument must be a function\n"+
+			filename+":39:1-2: must have at most two parameters (context.Context, struct)\n"+
+			filename+":39:69-69: unsupported response type \"ftl/failing.Response\"\n"+
+			filename+":44:22-27: first parameter must be of type context.Context but is ftl/failing.Request\n"+
+			filename+":44:37-43: second parameter must be a struct but is string\n"+
+			filename+":44:53-53: unsupported response type \"ftl/failing.Response\"\n"+
+			filename+":49:43-47: second parameter must not be ftl.Unit\n"+
+			filename+":49:59-59: unsupported response type \"ftl/failing.Response\"\n"+
+			filename+":54:1-2: first parameter must be context.Context\n"+
+			filename+":54:18-18: unsupported response type \"ftl/failing.Response\"\n"+
+			filename+":59:1-2: must have at most two results (struct, error)\n"+
+			filename+":59:41-44: unsupported request type \"ftl/failing.Request\"\n"+
+			filename+":64:1-2: must at least return an error\n"+
+			filename+":64:36-39: unsupported request type \"ftl/failing.Request\"\n"+
+			filename+":68:35-38: unsupported request type \"ftl/failing.Request\"\n"+
+			filename+":68:48-48: must return an error but is ftl/failing.Response\n"+
+			filename+":73:41-44: unsupported request type \"ftl/failing.Request\"\n"+
+			filename+":73:55-55: first result must be a struct but is string\n"+
+			filename+":73:63-63: must return an error but is string\n"+
+			filename+":73:63-63: second result must not be ftl.Unit\n"+
+			filename+":80:1-1: verb \"WrongResponse\" already exported\n"+
+			filename+":86:2-12: struct field unexported must be exported by starting with an uppercase letter",
 	)
 }
 

go-runtime/compile/testdata/failing/failing.go

@@ -9,6 +9,12 @@ import (
 
 var empty = ftl.Config[string]("")
 
+var goodConfig = ftl.Config[string]("FTL_ENDPOINT")
+var duplConfig = ftl.Config[string]("FTL_ENDPOINT")
+
+var goodSecret = ftl.Secret[string]("MY_SECRET")
+var duplSecret = ftl.Secret[string]("MY_SECRET")
+
 type Request struct {
 	BadParam error
 }