Correct the speeling of sentinel

src/common.cpp

@@ -1230,11 +1230,11 @@ wcstring debug_escape(const wcstring &in) {
             TEST(BRACE_SPACE)
             TEST(INTERNAL_SEPARATOR)
             TEST(VARIABLE_EXPAND_EMPTY)
-            TEST(EXPAND_SENTINAL)
+            TEST(EXPAND_SENTINEL)
             TEST(ANY_CHAR)
             TEST(ANY_STRING)
             TEST(ANY_STRING_RECURSIVE)
-            TEST(ANY_SENTINAL)
+            TEST(ANY_SENTINEL)
             default:
                 append_format(result, L"<\\x%02x>", c);
                 break;

src/common.h

@@ -736,7 +736,7 @@ struct enum_map {
     const wchar_t *const str;
 };
 
-/// Given a string return the matching enum. Return the sentinal enum if no match is made. The map
+/// Given a string return the matching enum. Return the sentinel enum if no match is made. The map
 /// must be sorted by the `str` member. A binary search is twice as fast as a linear search with 16
 /// elements in the map.
 template <typename T>

src/expand.h

@@ -96,7 +96,7 @@ enum : wchar_t {
     VARIABLE_EXPAND_EMPTY,
     /// This is a special pseudo-char that is not used other than to mark the end of the the special
     /// characters so we can sanity check the enum range.
-    EXPAND_SENTINAL
+    EXPAND_SENTINEL
 };
 
 /// These are the possible return values for expand_string.

src/wildcard.h

@@ -19,7 +19,7 @@ enum {
     ANY_STRING_RECURSIVE,
     /// This is a special pseudo-char that is not used other than to mark the
     /// end of the the special characters so we can sanity check the enum range.
-    ANY_SENTINAL
+    ANY_SENTINEL
 };
 
 /// Expand the wildcard by matching against the filesystem.