Updates

Author: seisman

pygmt/clib/session.py

@@ -1634,7 +1634,10 @@ def virtualfile_from_stringio(self, stringio: io.StringIO):
         >>> import io
         >>> from pygmt.clib import Session
         >>> stringio = io.StringIO(
-        ...     "H 24p Legend\nN 2\nS 0.1i c 0.15i p300/12 0.25p 0.3i My circle"
+        ...     "# Comment\n"
+        ...     "H 24p Legend\n"
+        ...     "N 2\n"
+        ...     "S 0.1i c 0.15i p300/12 0.25p 0.3i My circle\n"
         ... )
         >>> with Session() as lib:
         ...     with lib.virtualfile_from_stringio(stringio) as fin:

pygmt/helpers/utils.py

@@ -247,7 +247,9 @@ def data_kind(
     >>> data_kind(data=io.StringIO("TEXT1\nTEXT23\n"))
     'stringio'
     """
-    kind: Literal["arg", "file", "geojson", "grid", "image", "matrix", "vectors"]
+    kind: Literal[
+        "arg", "file", "geojson", "grid", "image", "matrix", "stringio", "vectors"
+    ]
     if isinstance(data, str | pathlib.PurePath) or (
         isinstance(data, list | tuple)
         and all(isinstance(_file, str | pathlib.PurePath) for _file in data)

pygmt/src/legend.py

@@ -89,16 +89,12 @@ def legend(
         if kwargs.get("F") is None:
             kwargs["F"] = box
 
-    match data_kind(spec):
-        case "vectors":  # spec is None
-            specfile = ""
-        case kind if kind == "file" and not is_nonstr_iter(spec):
-            specfile = spec
-        case "stringio":
-            specfile = spec
-        case _:
-            raise GMTInvalidInput(f"Unrecognized data type: {type(spec)}")
+    kind = data_kind(spec)
+    if kind not in {"vectors", "file", "stringio"}:
+        raise GMTInvalidInput(f"Unrecognized data type: {type(spec)}")
+    if kind == "file" and is_nonstr_iter(spec):
+        raise GMTInvalidInput("Only one legend specification file is allowed.")
 
     with Session() as lib:
-        with lib.virtualfile_in(data=specfile) as vintbl:
+        with lib.virtualfile_in(data=spec, required_data=False) as vintbl:
             lib.call_module(module="legend", args=build_arg_list(kwargs, infile=vintbl))