godoc: declare small victory over the punched card tyranny

At least inside this one package.

It's because golang.org/x/tools/cmd/godoc no longer has CLI support
as of golang/go#25443, it is now only a web server. Luckily, browsers
that display HTML pages are not constrained to the fixed width of
punched cards. On the contrary, they seem to embrace a wide variety of
arbitrary page widths, ranging from narrow to wide. This is in part due
to the proliferation of internet access on device form factors such as
the mobile phone, tablet, laptop, and desktop.

So the punchCardWidth constant is now unused and can be removed. This
is a followup to CL 141397 that removed most of the CLI support code,
including the function comment_textFunc, which was its only user. Same
goes for containsOnlySpace.

Updates golang/go#25443

Change-Id: I61fabe6ea801c88758fb2c6aefa70b53d52e2cb5
Reviewed-on: https://go-review.googlesource.com/c/tools/+/172975
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/godoc/godoc.go b/godoc/godoc.go
index 0681a5a..c84816a 100644
--- a/godoc/godoc.go
+++ b/godoc/godoc.go
@@ -355,26 +355,6 @@
 	return buf.String()
 }
 
-// punchCardWidth is the number of columns of fixed-width
-// characters to assume when wrapping text.  Very few people
-// use terminals or cards smaller than 80 characters, so 80 it is.
-// We do not try to sniff the environment or the tty to adapt to
-// the situation; instead, by using a constant we make sure that
-// godoc always produces the same output regardless of context,
-// a consistency that is lost otherwise.  For example, if we sniffed
-// the environment or tty, then http://golang.org/pkg/math/?m=text
-// would depend on the width of the terminal where godoc started,
-// which is clearly bogus.  More generally, the Unix tools that behave
-// differently when writing to a tty than when writing to a file have
-// a history of causing confusion (compare `ls` and `ls | cat`), and we
-// want to avoid that mistake here.
-const punchCardWidth = 80
-
-func containsOnlySpace(buf []byte) bool {
-	isNotSpace := func(r rune) bool { return !unicode.IsSpace(r) }
-	return bytes.IndexFunc(buf, isNotSpace) == -1
-}
-
 // sanitizeFunc sanitizes the argument src by replacing newlines with
 // blanks, removing extra blanks, and by removing trailing whitespace
 // and commas before closing parentheses.