unicode: fix case-mapping for roman numerals!!

Hurray!
Also fix the mystical U+0345 COMBINING GREEK YPOGEGRAMMENI,
so everyone is satisfied.
Also add a -local flag to use local files for faster turnaround
when debugging.

R=rsc
CC=golang-dev
https://golang.org/cl/4825054

src/pkg/unicode/letter_test.go

@@ -212,6 +212,10 @@ var caseTest = []caseT{
 	{UpperCase, 0x10450, 0x10450},
 	{LowerCase, 0x10450, 0x10450},
 	{TitleCase, 0x10450, 0x10450},
+
+	// Non-letters with case.
+	{LowerCase, 0x2161, 0x2171},
+	{UpperCase, 0x0345, 0x0399},
 }
 
 func TestIsLetter(t *testing.T) {

src/pkg/unicode/maketables.go

@@ -14,6 +14,7 @@ import (
 	"http"
 	"log"
 	"os"
+	"path/filepath"
 	"sort"
 	"strconv"
 	"strings"
@@ -54,10 +55,47 @@ var cases = flag.Bool("cases",
 var test = flag.Bool("test",
 	false,
 	"test existing tables; can be used to compare web data with package data")
+var localFiles = flag.Bool("local",
+	false,
+	"data files have been copied to current directory; for debugging only")
 
 var scriptRe = regexp.MustCompile(`^([0-9A-F]+)(\.\.[0-9A-F]+)? *; ([A-Za-z_]+)$`)
 var logger = log.New(os.Stderr, "", log.Lshortfile)
 
+type reader struct {
+	*bufio.Reader
+	fd   *os.File
+	resp *http.Response
+}
+
+func open(url string) *reader {
+	file := filepath.Base(url)
+	if *localFiles {
+		fd, err := os.Open(file)
+		if err != nil {
+			logger.Fatal(err)
+		}
+		return &reader{bufio.NewReader(fd), fd, nil}
+	}
+	resp, err := http.Get(*dataURL)
+	if err != nil {
+		logger.Fatal(err)
+	}
+	if resp.StatusCode != 200 {
+		logger.Fatalf("bad GET status for %s: %d", file, resp.Status)
+	}
+	return &reader{bufio.NewReader(resp.Body), nil, resp}
+
+}
+
+func (r *reader) close() {
+	if r.fd != nil {
+		r.fd.Close()
+	} else {
+		r.resp.Body.Close()
+	}
+}
+
 var category = map[string]bool{
 	// Nd Lu etc.
 	// We use one-character names to identify merged categories
@@ -192,7 +230,7 @@ func parseCategory(line string) (state State) {
 		char.letter(field[FSimpleUppercaseMapping], field[FCodePoint], field[FSimpleTitlecaseMapping])
 	case "Lt":
 		char.letter(field[FSimpleUppercaseMapping], field[FSimpleLowercaseMapping], field[FCodePoint])
-	case "Lm", "Lo":
+	default:
 		char.letter(field[FSimpleUppercaseMapping], field[FSimpleLowercaseMapping], field[FSimpleTitlecaseMapping])
 	}
 	switch {
@@ -272,14 +310,7 @@ func loadChars() {
 	if *dataURL == "" {
 		flag.Set("data", *url+"UnicodeData.txt")
 	}
-	resp, err := http.Get(*dataURL)
+	input := open(*dataURL)
-	if err != nil {
-		logger.Fatal(err)
-	}
-	if resp.StatusCode != 200 {
-		logger.Fatal("bad GET status for UnicodeData.txt", resp.Status)
-	}
-	input := bufio.NewReader(resp.Body)
 	var first uint32 = 0
 	for {
 		line, err := input.ReadString('\n')
@@ -310,21 +341,14 @@ func loadChars() {
 			first = 0
 		}
 	}
-	resp.Body.Close()
+	input.close()
 }
 
 func loadCasefold() {
 	if *casefoldingURL == "" {
 		flag.Set("casefolding", *url+"CaseFolding.txt")
 	}
-	resp, err := http.Get(*casefoldingURL)
+	input := open(*casefoldingURL)
-	if err != nil {
-		logger.Fatal(err)
-	}
-	if resp.StatusCode != 200 {
-		logger.Fatal("bad GET status for CaseFolding.txt", resp.Status)
-	}
-	input := bufio.NewReader(resp.Body)
 	for {
 		line, err := input.ReadString('\n')
 		if err != nil {
@@ -355,7 +379,7 @@ func loadCasefold() {
 		}
 		chars[p1].foldCase = int(p2)
 	}
-	resp.Body.Close()
+	input.close()
 }
 
 const progHeader = `// Generated by running
@@ -662,15 +686,7 @@ func printScriptOrProperty(doProps bool) {
 	if flaglist == "" {
 		return
 	}
-	var err os.Error
+	input := open(*url + file)
-	resp, err := http.Get(*url + file)
-	if err != nil {
-		logger.Fatal(err)
-	}
-	if resp.StatusCode != 200 {
-		logger.Fatal("bad GET status for ", file, ":", resp.Status)
-	}
-	input := bufio.NewReader(resp.Body)
 	for {
 		line, err := input.ReadString('\n')
 		if err != nil {
@@ -681,7 +697,7 @@ func printScriptOrProperty(doProps bool) {
 		}
 		parseScript(line[0:len(line)-1], table)
 	}
-	resp.Body.Close()
+	input.close()
 
 	// Find out which scripts to dump
 	list := strings.Split(flaglist, ",")
@@ -864,6 +880,16 @@ func getCaseState(i int) (c *caseState) {
 	case ch.titleCase:
 		c._case = CaseTitle
 	}
+	// Some things such as roman numeral U+2161 don't describe themselves
+	// as upper case, but have a lower case.  Second-guess them.
+	if c._case == CaseNone && ch.lowerCase != 0 {
+		c._case = CaseUpper
+	}
+	// Same in the other direction.
+	if c._case == CaseNone && ch.upperCase != 0 {
+		c._case = CaseLower
+	}
+
 	if ch.upperCase != 0 {
 		c.deltaToUpper = ch.upperCase - i
 	}

src/pkg/unicode/tables.go

@@ -5266,6 +5266,7 @@ var _CaseRanges = []CaseRange{
 	{0x028A, 0x028B, d{-217, 0, -217}},
 	{0x028C, 0x028C, d{-71, 0, -71}},
 	{0x0292, 0x0292, d{-219, 0, -219}},
+	{0x0345, 0x0345, d{84, 0, 84}},
 	{0x0370, 0x0373, d{UpperLower, UpperLower, UpperLower}},
 	{0x0376, 0x0377, d{UpperLower, UpperLower, UpperLower}},
 	{0x037B, 0x037D, d{130, 0, 130}},
@@ -5375,7 +5376,11 @@ var _CaseRanges = []CaseRange{
 	{0x212B, 0x212B, d{0, -8262, 0}},
 	{0x2132, 0x2132, d{0, 28, 0}},
 	{0x214E, 0x214E, d{-28, 0, -28}},
+	{0x2160, 0x216F, d{0, 16, 0}},
+	{0x2170, 0x217F, d{-16, 0, -16}},
 	{0x2183, 0x2184, d{UpperLower, UpperLower, UpperLower}},
+	{0x24B6, 0x24CF, d{0, 26, 0}},
+	{0x24D0, 0x24E9, d{-26, 0, -26}},
 	{0x2C00, 0x2C2E, d{0, 48, 0}},
 	{0x2C30, 0x2C5E, d{-48, 0, -48}},
 	{0x2C60, 0x2C61, d{UpperLower, UpperLower, UpperLower}},
@@ -5734,90 +5739,6 @@ var caseOrbit = []foldPair{
 	{0x2126, 0x03A9},
 	{0x212A, 0x004B},
 	{0x212B, 0x00C5},
-	{0x2160, 0x2170},
-	{0x2161, 0x2171},
-	{0x2162, 0x2172},
-	{0x2163, 0x2173},
-	{0x2164, 0x2174},
-	{0x2165, 0x2175},
-	{0x2166, 0x2176},
-	{0x2167, 0x2177},
-	{0x2168, 0x2178},
-	{0x2169, 0x2179},
-	{0x216A, 0x217A},
-	{0x216B, 0x217B},
-	{0x216C, 0x217C},
-	{0x216D, 0x217D},
-	{0x216E, 0x217E},
-	{0x216F, 0x217F},
-	{0x2170, 0x2160},
-	{0x2171, 0x2161},
-	{0x2172, 0x2162},
-	{0x2173, 0x2163},
-	{0x2174, 0x2164},
-	{0x2175, 0x2165},
-	{0x2176, 0x2166},
-	{0x2177, 0x2167},
-	{0x2178, 0x2168},
-	{0x2179, 0x2169},
-	{0x217A, 0x216A},
-	{0x217B, 0x216B},
-	{0x217C, 0x216C},
-	{0x217D, 0x216D},
-	{0x217E, 0x216E},
-	{0x217F, 0x216F},
-	{0x24B6, 0x24D0},
-	{0x24B7, 0x24D1},
-	{0x24B8, 0x24D2},
-	{0x24B9, 0x24D3},
-	{0x24BA, 0x24D4},
-	{0x24BB, 0x24D5},
-	{0x24BC, 0x24D6},
-	{0x24BD, 0x24D7},
-	{0x24BE, 0x24D8},
-	{0x24BF, 0x24D9},
-	{0x24C0, 0x24DA},
-	{0x24C1, 0x24DB},
-	{0x24C2, 0x24DC},
-	{0x24C3, 0x24DD},
-	{0x24C4, 0x24DE},
-	{0x24C5, 0x24DF},
-	{0x24C6, 0x24E0},
-	{0x24C7, 0x24E1},
-	{0x24C8, 0x24E2},
-	{0x24C9, 0x24E3},
-	{0x24CA, 0x24E4},
-	{0x24CB, 0x24E5},
-	{0x24CC, 0x24E6},
-	{0x24CD, 0x24E7},
-	{0x24CE, 0x24E8},
-	{0x24CF, 0x24E9},
-	{0x24D0, 0x24B6},
-	{0x24D1, 0x24B7},
-	{0x24D2, 0x24B8},
-	{0x24D3, 0x24B9},
-	{0x24D4, 0x24BA},
-	{0x24D5, 0x24BB},
-	{0x24D6, 0x24BC},
-	{0x24D7, 0x24BD},
-	{0x24D8, 0x24BE},
-	{0x24D9, 0x24BF},
-	{0x24DA, 0x24C0},
-	{0x24DB, 0x24C1},
-	{0x24DC, 0x24C2},
-	{0x24DD, 0x24C3},
-	{0x24DE, 0x24C4},
-	{0x24DF, 0x24C5},
-	{0x24E0, 0x24C6},
-	{0x24E1, 0x24C7},
-	{0x24E2, 0x24C8},
-	{0x24E3, 0x24C9},
-	{0x24E4, 0x24CA},
-	{0x24E5, 0x24CB},
-	{0x24E6, 0x24CC},
-	{0x24E7, 0x24CD},
-	{0x24E8, 0x24CE},
-	{0x24E9, 0x24CF},
 }
 
 // FoldCategory maps a category name to a table of
@@ -6102,4 +6023,4 @@ var FoldScript = map[string]*RangeTable{}
 // Range entries: 3391 16-bit, 659 32-bit, 4050 total.
 // Range bytes: 20346 16-bit, 7908 32-bit, 28254 total.
 
-// Fold orbit bytes: 147 pairs, 588 bytes
+// Fold orbit bytes: 63 pairs, 252 bytes