performs an `svn diff` but includes `svn annotate` metadata

blameDiff.sh

function blameDiff() {
	file="$1"
	rev1="$2"
	rev2="$3"

	#default to HEAD if omitted
	if [ -n "$rev1" ]
	then
		title1="(revision $rev1)"
	else
		title1="(working copy)"
		rev1='HEAD'
	fi
	if [ -n "$rev2" ]
	then
		title2="(revision $rev2)"
	else
		title2="(working copy)"
		rev2='HEAD'
	fi

	#check that the svn urls are the same
	tmp1="$(svn info -r $rev1 "$file" |\
		grep '^Relative URL' |\
		sed 's/Relative URL: //' \
	)"
	tmp2="$(svn info -r $rev2 "$file" |\
		grep '^Relative URL' |\
		sed 's/Relative URL: //' \
	)"
	if [ "$tmp1" != "$tmp2" ]
	then
		#if not, then one of these revisions is in another branch
		#lets have this in the output
		title1="($tmp1) $title1"
		title2="($tmp2) $title2"
	fi

#can just print this but you wont get deleted revision/blame
#	diff -u \
#		<(svn blame -r "$rev1" "$file") \
#		<(svn blame -r "$rev2" "$file") \
#	| sed "s|^--- .*$|--- $file $title1|" \
#	| sed "s|^+++ .*$|+++ $file $title2|"
#	return 0

	#an array of commitNumber|committer pairs for the file
	history=()
	#a map between elements in `history` and a list of line numbers changed.
	#each item in the list is a lineNumber|newLineNumber pair
	declare -A revisions

	#the sed match and replace expressions to pull data from the
	#diff-line-number&cat-line-number combo and give it to the cache
	grabData='^ *\([0-9]\+\)\t\([0-9]\+\)$'
	formatData='\2 \1'

	#for each revision between the ones given
	last=''
	while read -r line
	do
		#read in the revision number and submitter
		IFS=' |' read next by tmp <<<"$line"

		if [ -n "$last" ]
		then
			#save them
			history+=("$next $by")
			#associate and format the list
			revisions["${history[-1]}"]="$(\
				diff \
					--unchanged-line-format="%dn%c'\012'" \
					--new-line-format="?%c'\012'" \
					--old-line-format='' \
					<(svn cat -r "$last" "$file") \
					<(svn cat -r "$next" "$file") \
				| cat -n \
				| grep -v '?$' \
				| sed "s/$grabData/$formatData/" \
			)"
		fi

		#remember the last revision looked at
		last="$next"
	done <<<"$(
		svn log -r "$rev1:$rev2" "$file" \
		| grep '^r[0-9]\+ | ' \
		| sed 's/^r//' \
	)"

	#pull the full diff
	diff \
		--new-line-format='+%L' \
		--old-line-format='-%L' \
		--unchanged-line-format='=%L' \
		<(svn blame -r "$rev1" "$file") \
		<(svn blame -r "$rev2" "$file") \
	| {
		#header stuff
		echo "Index: $file"
		echo '==================================================================='
		echo "--- $file $title1"
		echo "+++ $file $title2"

		#count the line number we're up to for the original file
		origLine=0
		#count the line number we're up to for the new file
		newLine=0

		#keep a few of the output lines, and their line number contexts
		buffer=()
		origContext=()
		newContext=()

		#tells the script to print the buffer if <3;
		#the context lines around real differences
		printing=4
		#whether or not the next print needs to show line numbers
		needsContext=true

		#the sed match and replace expressions to pull data from diff
		#and give it to read
		grabData='^\([+=-]\)\( *[0-9]\+\)\( *[^ ]\+\)\(.*\)$'
		formatData='\1\v\2\v\3\v\4'

		#for each line in the full diff
		while read -r data
		do
			IFS=$'\v' read flag committed who line <<<"$(\
				sed $'s/\t/    /g' \
				<<<"$data" \
				| sed "s/$grabData/$formatData/" \
			)"
			#the last surviving revision of the line
			edited="$rev2"
			#who killed this line
			by=''

			case "$flag" in
			+)
				#a new line was introduced
				((++newLine))
				printing=0
			;;
			-)
				#an old line was removed
				((++origLine))
				printing=0
				#the line number that changes throughout history
				number="$origLine"
				#for each commit
				for revision in "${history[@]}"
				do
					#read in the two line numbers from the matching change
					number="$(grep "^$number " <<<"${revisions["$revision"]}")"
					IFS=' ' read edited by <<<"$revision"

					#not present; this was the revision where it was destroyed
					if [ -z "$number" ]
					then
						break
					fi

					#pull the new line number for the next revision
					IFS=' ' read tmp number <<<"$number"
				done
			;;
			=)
				#an old line continues to exist in the new file
				((++newLine))
				((++origLine))
				flag=' '
				((++printing))
			;;
			esac

			#format the line to print
			buffer+=("$(printf "%s %s:%-${#committed}s%s:%-${#who}s%s" \
				"$flag" \
				"$committed" \
				"$edited" \
				"$who" \
				"$by" \
				"$line" \
			)")
#can just end it here, but it will print the whole file/s
#			echo "${buffer[-1]}"
#			buffer=()
#			continue
			#and add the context
			origContext+=("$origLine")
			newContext+=("$newLine")

			if ((printing < 4))
			then
				if $needsContext
				then
					echo "@@ -${origContext[0]} +${newContext[0]} @@"
					needsContext=false
				fi

				#print all lines in the buffer
				for line in "${buffer[@]}"
				do
					echo "$line"
				done

				#and reset it
				origContext=()
				newContext=()
				buffer=()
			fi

			#if there are too many lines in the buffer
			if ((${#buffer[@]} > 3))
			then
				#remove the overflow
				origContext=("${origContext[@]:1}")
				newContext=("${newContext[@]:1}")
				buffer=("${buffer[@]:1}")
				#and note that we now need to show the context because of this
				needsContext=true
			fi
		done
	}
}

Usage; blameDiff <path> [rev1] [rev2] (unwrap the function in its own script, or source it/put it in your bashrc to call)

It basically reimplements the svn diff using just svn cat and regular diff to take into account the revision and line numbers, tracking exactly where in the history a given line was removed.
Even takes into account whether the files are in different branches and displays it as svn would.

Here's screenshots of the two following commands, with the code redacted for work-reasons.

~/data/<redacted>/svn-2.4.2/$ svn diff -r 6600 services/<redacted>.w3p | gvim -
~/data/<redacted>/svn-2.4.2/$ blameDiff services/<redacted>.w3p 6600 | gvim -

As you can see a bunch of extra info is given in the new format on the right; the first columns show ashley added a couple lines back in r6631, and deleted a whole bunch in r6639 originally committed by zes long ago @R6466&6483.