test: expand coverage across readers, writers, cmd, ui, diff and merge

Implements tests/_plans and previously deferred packages; updates plan
README with new coverage numbers.

pkg/writers/writer_test.go

@@ -70,3 +70,54 @@ func TestQuoteDefaultValue(t *testing.T) {
 		})
 	}
 }
+
+func TestQualifiedTableName(t *testing.T) {
+	tests := []struct {
+		schema, table string
+		flatten       bool
+		want          string
+	}{
+		{"", "t", false, "t"},
+		{"", "t", true, "t"},
+		{"s", "t", false, "s.t"},
+		{"s", "t", true, "s_t"},
+	}
+	for _, tt := range tests {
+		if got := QualifiedTableName(tt.schema, tt.table, tt.flatten); got != tt.want {
+			t.Errorf("%+v: got %q", tt, got)
+		}
+	}
+}
+
+func TestSanitizeFilename(t *testing.T) {
+	tests := []struct{ in, want string }{
+		{`"users"`, "users"},
+		{`'users'`, "users"},
+		{"`users`", "users"},
+		{"users [note: 'x']", "users"},
+		{"a/b\\c:d*e?f<g>h|i", "a_b_c_d_e_f_g_h_i"},
+		{"__a__b__", "a_b"},
+		{"  spaced  ", "spaced"},
+		{"ctl\x01char", "ctl_char"},
+	}
+	for _, tt := range tests {
+		if got := SanitizeFilename(tt.in); got != tt.want {
+			t.Errorf("%q: got %q want %q", tt.in, got, tt.want)
+		}
+	}
+}
+
+func TestSanitizeStructTagValue(t *testing.T) {
+	tests := []struct{ in, want string }{
+		{"name", "name"},
+		{"`na\"me'`", "name"},
+		{"users [note: 'x']", "users"},
+		{"tags[]", "tags[]"},
+		{"  padded  ", "padded"},
+	}
+	for _, tt := range tests {
+		if got := SanitizeStructTagValue(tt.in); got != tt.want {
+			t.Errorf("%q: got %q want %q", tt.in, got, tt.want)
+		}
+	}
+}