Fix tests and improve InvalidColumnType error message.

src/error.rs

@@ -54,7 +54,7 @@ pub enum Error {
 
     /// Error when the value of a particular column is requested, but the type of the result in
     /// that column cannot be converted to the requested Rust type.
-    InvalidColumnType,
+    InvalidColumnType(c_int, c_int),
 
     /// Error when a query that was expected to insert one row did not insert any or insert many.
     StatementChangedRows(c_int),
@@ -114,7 +114,7 @@ impl fmt::Display for Error {
             Error::GetFromStaleRow => write!(f, "Attempted to get a value from a stale row"),
             Error::InvalidColumnIndex(i) => write!(f, "Invalid column index: {}", i),
             Error::InvalidColumnName(ref name) => write!(f, "Invalid column name: {}", name),
-            Error::InvalidColumnType => write!(f, "Invalid column type"),
+            Error::InvalidColumnType(i, t) => write!(f, "Invalid column type {} at index: {}", t, i),
             Error::StatementChangedRows(i) => write!(f, "Query changed {} rows", i),
             Error::StatementFailedToInsertRow => write!(f, "Statement failed to insert new row"),
 
@@ -148,7 +148,7 @@ impl error::Error for Error {
             Error::GetFromStaleRow => "attempted to get a value from a stale row",
             Error::InvalidColumnIndex(_) => "invalid column index",
             Error::InvalidColumnName(_) => "invalid column name",
-            Error::InvalidColumnType => "invalid column type",
+            Error::InvalidColumnType(_, _) => "invalid column type",
             Error::StatementChangedRows(_) => "query inserted zero or more than one row",
             Error::StatementFailedToInsertRow => "statement failed to insert new row",
 
@@ -176,7 +176,7 @@ impl error::Error for Error {
             Error::GetFromStaleRow |
             Error::InvalidColumnIndex(_) |
             Error::InvalidColumnName(_) |
-            Error::InvalidColumnType |
+            Error::InvalidColumnType(_, _) |
             Error::InvalidPath(_) => None,
             Error::StatementChangedRows(_) => None,
             Error::StatementFailedToInsertRow => None,

src/lib.rs

@@ -1131,10 +1131,9 @@ impl<'stmt> Row<'stmt> {
         unsafe {
             let idx = try!(idx.idx(self.stmt));
 
-            if T::column_has_valid_sqlite_type(self.stmt.stmt, idx) {
-                FromSql::column_result(self.stmt.stmt, idx)
-            } else {
-                Err(Error::InvalidColumnType)
+            match T::column_has_valid_sqlite_type(self.stmt.stmt, idx) {
+                Ok(()) => FromSql::column_result(self.stmt.stmt, idx),
+                Err(e) => Err(e),
             }
         }
     }
@@ -1456,6 +1455,19 @@ mod test {
         }
     }
 
+    #[test]
+    #[should_panic]
+    fn test_rows_dropped() {
+        let db = checked_memory_handle();
+        db.execute_batch("CREATE TABLE foo(x INTEGER)").unwrap();
+        db.execute_batch("INSERT INTO foo(x) VALUES(1)").unwrap();
+
+        let mut stmt = db.prepare("SELECT x FROM foo").unwrap();
+        let row = stmt.query(&[]).unwrap().next().unwrap().unwrap();
+
+        assert_eq!(1i32, row.get(0));
+    }
+
     mod query_and_then_tests {
         extern crate libsqlite3_sys as ffi;
         use super::*;
@@ -1536,7 +1548,7 @@ mod test {
                 .collect();
 
             match bad_type.unwrap_err() {
-                Error::InvalidColumnType => (),
+                Error::InvalidColumnType(_, _) => (),
                 err => panic!("Unexpected error {}", err),
             }
 
@@ -1596,7 +1608,7 @@ mod test {
                 .collect();
 
             match bad_type.unwrap_err() {
-                CustomError::Sqlite(Error::InvalidColumnType) => (),
+                CustomError::Sqlite(Error::InvalidColumnType(_, _)) => (),
                 err => panic!("Unexpected error {}", err),
             }
 
@@ -1658,7 +1670,7 @@ mod test {
             });
 
             match bad_type.unwrap_err() {
-                CustomError::Sqlite(Error::InvalidColumnType) => (),
+                CustomError::Sqlite(Error::InvalidColumnType(_, _)) => (),
                 err => panic!("Unexpected error {}", err),
             }
 

src/types/chrono.rs

@@ -27,7 +27,7 @@ impl FromSql for NaiveDate {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
         String::column_has_valid_sqlite_type(stmt, col)
     }
 }
@@ -55,7 +55,7 @@ impl FromSql for NaiveTime {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
         String::column_has_valid_sqlite_type(stmt, col)
     }
 }
@@ -86,7 +86,7 @@ impl FromSql for NaiveDateTime {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
         String::column_has_valid_sqlite_type(stmt, col)
     }
 }
@@ -118,7 +118,7 @@ impl FromSql for DateTime<UTC> {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
         String::column_has_valid_sqlite_type(stmt, col)
     }
 }
@@ -130,7 +130,7 @@ impl FromSql for DateTime<Local> {
         Ok(utc_dt.with_timezone(&Local))
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
         DateTime::<UTC>::column_has_valid_sqlite_type(stmt, col)
     }
 }

src/types/mod.rs

@@ -83,8 +83,17 @@ pub trait FromSql: Sized {
     /// the type reported by SQLite matches a type suitable for Self. This method is used
     /// by `Row::get_checked` to confirm that the column contains a valid type before
     /// attempting to retrieve the value.
-    unsafe fn column_has_valid_sqlite_type(_: *mut sqlite3_stmt, _: c_int) -> bool {
-        true
+    unsafe fn column_has_valid_sqlite_type(_: *mut sqlite3_stmt, _: c_int) -> Result<()> {
+        Ok(())
+    }
+}
+
+unsafe fn column_has_expected_typed(stmt: *mut sqlite3_stmt, col: c_int, expected_type: c_int) -> Result<()> {
+    let actual_type = sqlite3_column_type(stmt, col);
+    if actual_type == expected_type {
+        Ok(())
+    } else {
+        Err(Error::InvalidColumnType(col, actual_type))
     }
 }
 
@@ -197,8 +206,8 @@ macro_rules! raw_from_impl(
                 Ok(ffi::$f(stmt, col))
             }
 
-            unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
-                sqlite3_column_type(stmt, col) == $c
+            unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
+                column_has_expected_typed(stmt, col, $c)
             }
         }
     )
@@ -216,8 +225,8 @@ impl FromSql for bool {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
-        sqlite3_column_type(stmt, col) == ffi::SQLITE_INTEGER
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
+        column_has_expected_typed(stmt, col, ffi::SQLITE_INTEGER)
     }
 }
 
@@ -233,8 +242,8 @@ impl FromSql for String {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
-        sqlite3_column_type(stmt, col) == ffi::SQLITE_TEXT
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
+        column_has_expected_typed(stmt, col, ffi::SQLITE_TEXT)
     }
 }
 
@@ -253,8 +262,8 @@ impl FromSql for Vec<u8> {
         Ok(from_raw_parts(mem::transmute(c_blob), len).to_vec())
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
-        sqlite3_column_type(stmt, col) == ffi::SQLITE_BLOB
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
+        column_has_expected_typed(stmt, col, ffi::SQLITE_BLOB)
     }
 }
 
@@ -267,11 +276,14 @@ impl<T: FromSql> FromSql for Option<T> {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
-        sqlite3_column_type(stmt, col) == ffi::SQLITE_NULL ||
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
+        if sqlite3_column_type(stmt, col) == ffi::SQLITE_NULL {
+            Ok(())
+        } else {
             T::column_has_valid_sqlite_type(stmt, col)
         }
     }
+}
 
 /// Dynamic type value (http://sqlite.org/datatype3.html)
 /// Value's type is dictated by SQLite (not by the caller).
@@ -297,7 +309,7 @@ impl FromSql for Value {
             ffi::SQLITE_FLOAT => Ok(Value::Real(ffi::sqlite3_column_double(stmt, col))),
             ffi::SQLITE_NULL => Ok(Value::Null),
             ffi::SQLITE_BLOB => FromSql::column_result(stmt, col).map(Value::Blob),
-            _ => Err(Error::InvalidColumnType),
+            ct => Err(Error::InvalidColumnType(col, ct)),
         }
     }
 }
@@ -371,7 +383,7 @@ mod test {
     fn test_mismatched_types() {
         fn is_invalid_column_type(err: Error) -> bool {
             match err {
-                Error::InvalidColumnType => true,
+                Error::InvalidColumnType(_, _) => true,
                 _ => false,
             }
         }

src/types/serde_json.rs

@@ -31,7 +31,7 @@ impl FromSql for Value {
                 let blob = try!(Vec::<u8>::column_result(stmt, col));
                 serde_json::from_slice(&blob)
             }
-            _ => return Err(Error::InvalidColumnType),
+            ct => return Err(Error::InvalidColumnType(col, ct)),
         };
         value_result.map_err(|err| Error::FromSqlConversionFailure(Box::new(err)))
     }

src/types/time.rs

@@ -24,7 +24,7 @@ impl FromSql for time::Timespec {
         }
     }
 
-    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> bool {
+    unsafe fn column_has_valid_sqlite_type(stmt: *mut sqlite3_stmt, col: c_int) -> Result<()> {
         String::column_has_valid_sqlite_type(stmt, col)
     }
 }

src/vtab/csvtab.rs

@@ -267,7 +267,8 @@ mod test {
                                     WHERE v1.rowid < v2.rowid")
                           .unwrap();
 
-            let row = s.query(&[]).unwrap().next().unwrap().unwrap();
+            let mut rows = s.query(&[]).unwrap();
+            let row = rows.next().unwrap().unwrap();
             assert_eq!(row.get::<i32, i32>(0), 2);
         }
         db.execute_batch("DROP TABLE vtab").unwrap();

src/vtab/int_array.rs

@@ -173,7 +173,6 @@ mod test {
             }
         }
 
-        s.reset_if_needed();
         p1.borrow_mut().clear();
         p2.borrow_mut().clear();
         p3.borrow_mut().clear();
@@ -182,18 +181,19 @@ mod test {
         p3.borrow_mut().append(&mut vec![-5, -10]);
 
         {
-            let row = s.query(&[]).unwrap().next().unwrap().unwrap();
+            let mut rows = s.query(&[]).unwrap();
+            let row = rows.next().unwrap().unwrap();
             assert_eq!(1, row.get(0));
             assert_eq!(11, row.get(1));
             assert_eq!(-5, row.get(2));
         }
 
-        s.reset_if_needed();
         p2.borrow_mut().clear();
         p3.borrow_mut().clear();
         p2.borrow_mut().append(&mut vec![3, 4, 5]);
         p3.borrow_mut().append(&mut vec![0, -5]);
-        assert!(s.query(&[]).unwrap().next().is_none());
+        let mut rows = s.query(&[]).unwrap();
+        assert!(rows.next().is_none());
 
         int_array::drop_int_array(&db, "ex1").unwrap();
         int_array::drop_int_array(&db, "ex2").unwrap();