Date precision (#6359)

* Remove month/year only formats from ParseDateStringAsTime
* Add precision field to Date and handle parsing year/month-only dates
* Add date precision columns for date columns
* Adjust UI to account for fuzzy dates

pkg/models/date_test.go

@@ -0,0 +1,50 @@
+package models
+
+import (
+	"testing"
+	"time"
+)
+
+func TestParseDateStringAsTime(t *testing.T) {
+	tests := []struct {
+		name        string
+		input       string
+		output      Date
+		expectError bool
+	}{
+		// Full date formats (existing support)
+		{"RFC3339", "2014-01-02T15:04:05Z", Date{Time: time.Date(2014, 1, 2, 15, 4, 5, 0, time.UTC), Precision: DatePrecisionDay}, false},
+		{"Date only", "2014-01-02", Date{Time: time.Date(2014, 1, 2, 0, 0, 0, 0, time.UTC), Precision: DatePrecisionDay}, false},
+		{"Date with time", "2014-01-02 15:04:05", Date{Time: time.Date(2014, 1, 2, 15, 4, 5, 0, time.UTC), Precision: DatePrecisionDay}, false},
+
+		// Partial date formats (new support)
+		{"Year-Month", "2006-08", Date{Time: time.Date(2006, 8, 1, 0, 0, 0, 0, time.UTC), Precision: DatePrecisionMonth}, false},
+		{"Year only", "2014", Date{Time: time.Date(2014, 1, 1, 0, 0, 0, 0, time.UTC), Precision: DatePrecisionYear}, false},
+
+		// Invalid formats
+		{"Invalid format", "not-a-date", Date{}, true},
+		{"Empty string", "", Date{}, true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result, err := ParseDate(tt.input)
+
+			if tt.expectError {
+				if err == nil {
+					t.Errorf("Expected error for input %q, but got none", tt.input)
+				}
+				return
+			}
+
+			if err != nil {
+				t.Errorf("Unexpected error for input %q: %v", tt.input, err)
+				return
+			}
+
+			if !result.Time.Equal(tt.output.Time) || result.Precision != tt.output.Precision {
+				t.Errorf("For input %q, expected output %+v, got %+v", tt.input, tt.output, result)
+			}
+		})
+	}
+}