don't fail parsing of module name in case of leading comment

pine-vm · Jan 27, 2025 · e2615f2 · e2615f2
1 parent 0c12b6d
commit e2615f2
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Showing 2 changed files with 78 additions and 5 deletions.
diff --git a/implement/pine/ElmSyntax/ElmModule.cs b/implement/pine/ElmSyntax/ElmModule.cs
@@ -163,21 +163,54 @@ public static Result<string, IReadOnlyList<string>> ParseModuleName(ReadOnlyMemo
 
     public static Result<string, IReadOnlyList<string>> ParseModuleName(string moduleText)
     {
+        // This pattern removes all leading:
+        //   - whitespace (\s)
+        //   - single-line comments (--... up to end of line)
+        //   - multi-line comments ({- ... -}), which can span multiple lines
+        // The * at the end repeats that pattern until it no longer matches.
+        // Using RegexOptions.Singleline so '.' can match across newlines within {- -}.
+        var textWithoutLeadingComments = Regex.Replace(
+            moduleText,
+            pattern: @"\A(?:
+                      \s+                                 # skip any whitespace
+                    | --[^\r\n]*(?:\r\n|\r|\n|$)         # skip single-line comment + EOL
+                    | \{\-[\s\S]*?\-\}                   # skip multi-line comment
+                  )*",
+            replacement: "",
+            options: RegexOptions.IgnorePatternWhitespace | RegexOptions.Singleline);
+
         {
-            var match = Regex.Match(moduleText, @"^(port\s+)?module\s+([\w.]+)\s+exposing");
+            // Match: optional `port `, then `module`, then a dotted identifier, then `exposing`.
+            // Example:  port module MyModule exposing
+
+            var match =
+                Regex.Match(
+                    textWithoutLeadingComments,
+                    @"^(port\s+)?module\s+([\w.]+)\s+exposing",
+                    RegexOptions.Singleline);
 
             if (match.Success)
             {
-                return Result<string, IReadOnlyList<string>>.ok(match.Groups[2].Value.Split('.'));
+                return Result<string, IReadOnlyList<string>>.ok(
+                    match.Groups[2].Value.Split('.'));
             }
         }
 
         {
-            var match = Regex.Match(moduleText, @"^effect\s+module\s+([\w.]+)\s+(where|exposing)");
+            // Match: `effect module`, then dotted identifier, then `where` or `exposing`.
+            // Example:  effect module MyModule where ...
+            //           effect module MyModule exposing ...
+
+            var match =
+                Regex.Match(
+                    textWithoutLeadingComments,
+                    @"^effect\s+module\s+([\w.]+)\s+(where|exposing)",
+                    RegexOptions.Singleline);
 
             if (match.Success)
             {
-                return Result<string, IReadOnlyList<string>>.ok(match.Groups[1].Value.Split('.'));
+                return Result<string, IReadOnlyList<string>>.ok(
+                    match.Groups[1].Value.Split('.'));
             }
         }
 

diff --git a/implement/test-elm-time/ElmSyntaxTests.cs b/implement/test-elm-time/ElmSyntaxTests.cs
@@ -61,6 +61,20 @@ module Elm.JsArray
                 (IReadOnlyList<string>)["Elm", "JsArray"]
             },
 
+            new
+            {
+                moduleText =
+                """
+                {-| Multi-line comment
+                -}
+
+                module Test exposing ( .. )
+                """,
+
+                expectedModuleName =
+                (IReadOnlyList<string>)["Test"]
+            },
+
             new
             {
                 moduleText =
@@ -87,7 +101,8 @@ module Elm.JsArray
 
             if (parseModuleNameResult.IsErrOrNull() is { } err)
             {
-                Assert.Fail("Failed to parse module name: " + err);
+                Assert.Fail(
+                    "Failed to parse module name: " + err + "\nmodule text:\n" + testCase.moduleText);
             }
 
             if (parseModuleNameResult.IsOkOrNull() is not { } parsedName)
@@ -102,6 +117,31 @@ module Elm.JsArray
         }
     }
 
+    [TestMethod]
+    public void Parse_Elm_module_name_ignores_string_literal_content()
+    {
+        var moduleText =
+            """"
+            -- module TestModule exposing (..)
+
+            test =
+                [ ""
+                , """
+            module Bytes.Decode exposing (..)
+
+            """ ]
+
+                
+            """";
+
+        var parseModuleNameResult =
+            ElmModule.ParseModuleName(moduleText);
+
+        Assert.IsTrue(
+            parseModuleNameResult.IsErr(),
+            message: "Expected error");
+    }
+
     [TestMethod]
     public void Parse_Elm_module_text_imports()
     {