indicator is now an option in error

Changelog.md

@@ -11,6 +11,7 @@
 * `DataType::utf16_len` now returns `Option<NonZeroUSize>` instead of `Option<usize>`
 * `DataType::column_size` now returns `Option<NonZeroUSize>` instead of `usize`
 * `BufferDesc::from_data_type` now returns `None` for variadic types without upper bound instead of a zero sized buffer.
+* `Indicator::value_len` now is named `Indicator::length`.
 
 ## 3.0.1
 

odbc-api/src/buffers/columnar.rs

@@ -113,7 +113,7 @@ where
                 col_buffer
                     .has_truncated_values(*self.num_rows)
                     .map(|indicator| TruncationInfo {
-                        indicator,
+                        indicator: indicator.length(),
                         buffer_index,
                     })
             })

odbc-api/src/buffers/indicator.rs

@@ -1,5 +1,3 @@
-use std::fmt::Display;
-
 use odbc_sys::{NO_TOTAL, NULL_DATA};
 
 /// Indicates existence and length of a value.
@@ -14,16 +12,6 @@ pub enum Indicator {
     Length(usize),
 }
 
-impl Display for Indicator {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        match self {
-            Indicator::Null => write!(f, "Null"),
-            Indicator::NoTotal => write!(f, "No Total"),
-            Indicator::Length(length) => write!(f, "{length}"),
-        }
-    }
-}
-
 impl Indicator {
     /// Creates an indicator from an `isize` indicator value returned by ODBC. Users of this crate
     /// have likely no need to call this method.
@@ -69,7 +57,7 @@ impl Indicator {
     }
 
     /// If the indicator is [`Indicator::Length`] this is [`Some`].
-    pub fn value_len(self) -> Option<usize> {
+    pub fn length(self) -> Option<usize> {
         if let Indicator::Length(len) = self {
             Some(len)
         } else {

odbc-api/src/cursor.rs

@@ -238,7 +238,7 @@ impl<'s> CursorRow<'s> {
         }
         // We did get the complete value, including the terminating zero. Let's resize the buffer to
         // match the retrieved value exactly (excluding terminating zero).
-        if let Some(len_in_bytes) = target.indicator().value_len() {
+        if let Some(len_in_bytes) = target.indicator().length() {
             // Since the indicator refers to value length without terminating zero, and capacity is
             // including the terminating zero this also implicitly drops the terminating zero at the
             // end of the buffer.
@@ -395,8 +395,8 @@ pub unsafe trait RowSetBuffer {
 
 /// Returned by [`RowSetBuffer::find_truncation`]. Contains information about the truncation found.
 pub struct TruncationInfo {
-    /// Indicator of the complete untruncated value.
-    pub indicator: Indicator,
+    /// Length of the untruncated value if known
+    pub indicator: Option<usize>,
     /// Zero based buffer index of the column in which the truncation occurred.
     pub buffer_index: usize,
 }

odbc-api/src/error.rs

@@ -2,10 +2,7 @@ use std::io;
 
 use thiserror::Error as ThisError;
 
-use crate::{
-    buffers::Indicator,
-    handles::{log_diagnostics, Diagnostics, Record as DiagnosticRecord, SqlResult},
-};
+use crate::handles::{log_diagnostics, Diagnostics, Record as DiagnosticRecord, SqlResult};
 
 /// Error indicating a failed allocation for a column buffer
 #[derive(Debug)]
@@ -50,7 +47,8 @@ pub enum Error {
     #[error(
         "No Diagnostics available. The ODBC function call to {} returned an error. Sadly neither \
         the ODBC driver manager, nor the driver were polite enough to leave a diagnostic record \
-        specifying what exactly went wrong.", function
+        specifying what exactly went wrong.",
+        function
     )]
     NoDiagnostics {
         /// ODBC API call which returned error without producing a diagnostic record.
@@ -127,17 +125,14 @@ pub enum Error {
     },
     #[error(
         "A value (at least one) is too large to be written into the allocated buffer without \
-        truncation. Size in bytes indicated by ODBC driver: {indicator}"
+        truncation. Size in bytes indicated by ODBC driver: {indicator:?}"
     )]
     TooLargeValueForBuffer {
-        /// Length of the complete value in bytes as reported by the ODBC driver.
-        ///
-        /// Only variants [`Indicator::NoTotal`], or [`Indicator::Length`] should be able to cause
-        /// this error.
-        indicator: Indicator,
+        /// Length of the complete value in bytes as reported by the ODBC driver. If the length is
+        /// not known, this is `None`.
+        indicator: Option<usize>,
         /// Index of the buffer in which the truncation occurred.
         buffer_index: usize,
-
     },
 }
 

odbc-api/tests/integration.rs

@@ -3528,7 +3528,7 @@ fn detect_truncated_output_in_bulk_fetch(profile: &Profile) {
     assert!(matches!(
         cursor.fetch_with_truncation_check(true),
         Err(Error::TooLargeValueForBuffer {
-            indicator: Indicator::Length(10),
+            indicator: Some(10),
             buffer_index: 0,
         })
     ))

odbcsv/src/main.rs

@@ -583,7 +583,7 @@ fn cursor_to_csv(
 fn provide_context_for_truncation_error(error: odbc_api::Error) -> Error {
     match error {
         odbc_api::Error::TooLargeValueForBuffer {
-            indicator: Indicator::Length(required),
+            indicator: Some(required),
             buffer_index,
         } => {
             anyhow!(
@@ -595,7 +595,7 @@ fn provide_context_for_truncation_error(error: odbc_api::Error) -> Error {
             )
         }
         odbc_api::Error::TooLargeValueForBuffer {
-            indicator: Indicator::NoTotal,
+            indicator: None,
             buffer_index,
         } => {
             anyhow!(
@@ -607,10 +607,6 @@ fn provide_context_for_truncation_error(error: odbc_api::Error) -> Error {
                 large the value that caused the truncation is."
             )
         }
-        odbc_api::Error::TooLargeValueForBuffer {
-            indicator: Indicator::Null,
-            buffer_index,
-        } => unreachable!(),
         other => other.into(),
     }
 }