Fixed small typos in files of the optimizer

datafusion/optimizer/src/eliminate_cross_join.rs

@@ -38,7 +38,7 @@ impl EliminateCrossJoin {
     }
 }
 
-/// Attempt to reorder join tp eliminate cross joins to inner joins.
+/// Attempt to reorder join to eliminate cross joins to inner joins.
 /// for queries:
 /// 'select ... from a, b where a.x = b.y and b.xx = 100;'
 /// 'select ... from a, b where (a.x = b.y and b.xx = 100) or (a.x = b.y and b.xx = 200);'

datafusion/optimizer/src/eliminate_outer_join.rs

@@ -33,7 +33,7 @@ use std::sync::Arc;
 /// Attempt to replace outer joins with inner joins.
 ///
 /// Outer joins are typically more expensive to compute at runtime
-/// than inner joins and prevent various forms fo predicate pushdown
+/// than inner joins and prevent various forms of predicate pushdown
 /// and other optimizations, so removing them if possible is beneficial.
 ///
 /// Inner joins filter out rows that do match. Outer joins pass rows
@@ -44,7 +44,7 @@ use std::sync::Arc;
 /// For example, in the `select ... from a left join b on ... where b.xx = 100;`
 ///
 /// For rows when `b.xx` is null (as it would be after an outer join),
-/// the `b.xx = 100` predicate filters them out and there there is no
+/// the `b.xx = 100` predicate filters them out and there is no
 /// need to produce null rows for output.
 ///
 /// Generally, an outer join can be rewritten to inner join if the

datafusion/optimizer/src/optimizer.rs

@@ -63,7 +63,7 @@ pub trait OptimizerRule {
 
     /// How should the rule be applied by the optimizer? See comments on [`ApplyOrder`] for details.
     ///
-    /// If a rule use default None, its should traverse recursively plan inside itself
+    /// If a rule use default None, it should traverse recursively plan inside itself
     fn apply_order(&self) -> Option<ApplyOrder> {
         None
     }

datafusion/optimizer/src/simplify_expressions/expr_simplifier.rs

@@ -154,7 +154,7 @@ struct ConstEvaluator<'a> {
     /// traversal when we are N levels deep in the tree, one entry for
     /// this Expr and each of its parents.
     ///
-    /// After visiting all siblings if `can_evauate.top()`` is true, that
+    /// After visiting all siblings if `can_evaluate.top()` is true, that
     /// means there were no non evaluatable siblings (or their
     /// descendants) so this `Expr` can be evaluated
     can_evaluate: Vec<bool>,