add warning and return an empty range if not a worksheet

src/xlsx/cells_reader.rs

@@ -39,6 +39,7 @@ impl<'a> XlsxCellReader<'a> {
     ) -> Result<Self, XlsxError> {
         let mut buf = Vec::with_capacity(1024);
         let mut dimensions = Dimensions::default();
+        let mut sh_type = None;
         'xml: loop {
             buf.clear();
             match xml.read_event_into(&mut buf).map_err(XlsxError::Xml)? {
@@ -57,9 +58,19 @@ impl<'a> XlsxCellReader<'a> {
                         return Err(XlsxError::UnexpectedNode("dimension"));
                     }
                     b"sheetData" => break,
-                    _ => (),
+                    typ => {
+                        if sh_type.is_none() {
+                            sh_type = Some(xml.decoder().decode(typ)?.to_string());
+                        }
+                    }
                 },
-                Event::Eof => return Err(XlsxError::XmlEof("sheetData")),
+                Event::Eof => {
+                    if let Some(typ) = sh_type {
+                        return Err(XlsxError::NotAWorksheet(typ));
+                    } else {
+                        return Err(XlsxError::XmlEof("worksheet"));
+                    }
+                }
                 _ => (),
             }
         }

src/xlsx/mod.rs

@@ -87,6 +87,8 @@ pub enum XlsxError {
     WorksheetNotFound(String),
     /// Table not found
     TableNotFound(String),
+    /// The specified sheet is not a worksheet
+    NotAWorksheet(String),
 }
 
 from_err!(std::io::Error, XlsxError, Io);
@@ -136,6 +138,7 @@ impl std::fmt::Display for XlsxError {
             XlsxError::WorksheetNotFound(n) => write!(f, "Worksheet '{n}' not found"),
             XlsxError::Password => write!(f, "Workbook is password protected"),
             XlsxError::TableNotFound(n) => write!(f, "Table '{n}' not found"),
+            XlsxError::NotAWorksheet(typ) => write!(f, "Expecting a worksheet, got {typ}"),
         }
     }
 }
@@ -854,7 +857,14 @@ impl<RS: Read + Seek> Xlsx<RS> {
         &'a mut self,
         name: &str,
     ) -> Result<Range<DataRef<'a>>, XlsxError> {
-        let mut cell_reader = self.worksheet_cells_reader(name)?;
+        let mut cell_reader = match self.worksheet_cells_reader(name) {
+            Ok(reader) => reader,
+            Err(XlsxError::NotAWorksheet(typ)) => {
+                log::warn!("'{typ}' not a valid worksheet");
+                return Ok(Range::default());
+            }
+            Err(e) => return Err(e),
+        };
         let len = cell_reader.dimensions().len();
         let mut cells = Vec::new();
         if len < 100_000 {
@@ -928,7 +938,14 @@ impl<RS: Read + Seek> Reader<RS> for Xlsx<RS> {
     }
 
     fn worksheet_formula(&mut self, name: &str) -> Result<Range<String>, XlsxError> {
-        let mut cell_reader = self.worksheet_cells_reader(name)?;
+        let mut cell_reader = match self.worksheet_cells_reader(name) {
+            Ok(reader) => reader,
+            Err(XlsxError::NotAWorksheet(typ)) => {
+                warn!("'{typ}' not a worksheet");
+                return Ok(Range::default());
+            }
+            Err(e) => return Err(e),
+        };
         let len = cell_reader.dimensions().len();
         let mut cells = Vec::new();
         if len < 100_000 {

tests/test.rs

@@ -1691,6 +1691,14 @@ fn issue_420_empty_s_attribute() {
     );
 }
 
+#[test]
+fn issue_438_charts() {
+    let mut excel: Xlsx<_> = wb("issue438.xlsx");
+    let _range = excel
+        .worksheet_range("Chart1")
+        .expect("could not open worksheet range");
+}
+
 #[test]
 fn isssue_446_formulas() {
     let mut excel: Xlsx<_> = wb("issue446.xlsx");