Fix DomainError when parsing DateTime (#22198)

* Fix DomainError when parsing DateTime

* Converted tests into a testset

Author: omus

base/dates/io.jl

@@ -111,7 +111,15 @@ end
 @inline function tryparsenext(d::DatePart{'s'}, str, i, len)
     ms, ii = tryparsenext_base10(str, i, len, min_width(d), max_width(d))
     if !isnull(ms)
-        ms = Nullable{Int64}(get(ms) * 10 ^ (3 - (ii - i)))
+        val = get(ms)
+        len = ii - i
+        if len > 3
+            val, r = divrem(val, Int64(10) ^ (len - 3))
+            r == 0 || throw(InexactError())
+        else
+            val *= Int64(10) ^ (3 - len)
+        end
+        ms = Nullable{Int64}(val)
     end
     return ms, ii
 end

test/dates/io.jl

@@ -432,3 +432,16 @@ end
 
 # Issue #21504
 @test isnull(tryparse(Dates.Date, "0-1000"))
+
+# Issue #22100
+@testset "parse milliseconds" begin
+    @test Dates.DateTime("2017-Mar-17 00:00:00.0000", "y-u-d H:M:S.s") == Dates.DateTime(2017, 3, 17)
+    @test Dates.parse_components(".1", Dates.DateFormat(".s")) == [Dates.Millisecond(100)]
+    @test Dates.parse_components(".12", Dates.DateFormat(".s")) == [Dates.Millisecond(120)]
+    @test Dates.parse_components(".123", Dates.DateFormat(".s")) == [Dates.Millisecond(123)]
+    @test Dates.parse_components(".1230", Dates.DateFormat(".s")) == [Dates.Millisecond(123)]
+    @test_throws InexactError Dates.parse_components(".1234", Dates.DateFormat(".s"))
+
+    # Ensure that no overflow occurs when using Int32 literals: Int32(10)^10
+    @test Dates.parse_components("." * rpad(999, 10, '0'), Dates.DateFormat(".s")) == [Dates.Millisecond(999)]
+end