用 grep 捕获整个 function

Question

想要用另一个替换文件中的 function。 我有这个：

文件 1.cpp：

void Component::initialize()
{
    my_component = new ComponentClass();
}

和 File2.cpp：

void Component::initialize()
{
    if (doInit)
    {
        my_component = new ComponentClass();
    }
    else
    {
        my_component.ptr = null;
    }
}

我尝试编写脚本，但我的 grep 没有提供结果：

Old=$(grep -Eo "void Component::initialize(\n|.)*(^})*?" file1.cpp)
echo "Old=$Old" # empty variable

# My purpose is to do this :
New=$(grep -Eo "void Component::initialize(\n|.)*(^})*?" file2.cpp)
sed -i "s/$Old/$New/g" file1.cpp

Answer 1

#!/usr/bin/awk -f

/^void Component::initialize\(\)$/ {
    temp = $0

    while (!/^}/ && getline > 0)
        temp = temp ORS $0

    if (NR == FNR) {
        new = temp
        nextfile
    }

    $0 = new
}

NR != FNR

用法：

awk -f script.awk file{2,1}.cpp

Answer 2

请耐心等待。

此处第 4.23.3 节中介绍了解决此问题的通用方法。

下面的脚本试图合并并演示该方法。

#!/bin/bash

DBG=1

###
### Code segment to be replaced
###
file1="File1.cpp"
rm -f "${file1}"
cat >"${file1}" <<"EnDoFiNpUt"
void Component::initialize()
{
    my_component = new ComponentClass();
}
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 1"

###
### Code segment to be used as replacement
###
file2="File2.cpp"
rm -f "${file2}"
cat >"${file2}" <<"EnDoFiNpUt"
void Component::initialize()
{
    if (doInit)
    {
        my_component = new ComponentClass();
    }
    else
    {
        my_component.ptr = null;
    }
}
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 2"

###
### Create demo input file
###
testfile="Test_INPUT.cpp"
rm -f "${testfile}"
{
    echo "
other code1()
{
    doing other things
    doing more things
    doing extra things
} 
"
    cat "${file1}"

echo "
other code2()
{
    creating other things
    creating more things
    creating extra things
} 
"
} >>"${testfile}"

test ${DBG} -eq 1 && echo "fence 3"

###
### Create editing specification file
###
{
    cat "${file1}"
    echo "----"
    cat "${file2}"
} >findrep.txt

test ${DBG} -eq 1 && echo "fence 4"


###
### sed script to create editing instructions to apply aove editing specification file
###
cat >"blockrep.sed" <<"EnDoFiNpUt"
#SOURCE:    https://www.linuxtopia.org/online_books/linux_tool_guides/the_sed_faq/sedfaq4_013.html
#
# filename: blockrep.sed
#   author: Paolo Bonzini
# Requires:
#    (1) blocks to find and replace, e.g., findrep.txt
#    (2) an input file to be changed, input.file
#
# blockrep.sed creates a second sed script, custom.sed,
# to find the lines above the row of 4 hyphens, globally
# replacing them with the lower block of text. GNU sed
# is recommended but not required for this script.
#
# Loop on the first part, accumulating the `from' text
# into the hold space.
:a
/^----$/! {
   # Escape slashes, backslashes, the final newline and
   # regular expression metacharacters.
   s,[/\[.*],\\&,g
   s/$/\\/
   H
   #
   # Append N cmds needed to maintain the sliding window.
   x
   1 s,^.,s/,
   1! s/^/N\
/
   x
   n
   ba
}
#
# Change the final backslash to a slash to separate the
# two sides of the s command.
x
s,\\$,/,
x
#
# Until EOF, gather the substitution into hold space.
:b
n
s,[/\],\\&,g
$! s/$/\\/
H
$! bb
#
# Start the RHS of the s command without a leading
# newline, add the P/D pair for the sliding window, and
# print the script.
g
s,/\n,/,
s,$,/\
P\
D,p
#---end of script---
EnDoFiNpUt

test ${DBG} -eq 1 && echo "fence 5"


sed --debug -nf blockrep.sed findrep.txt >custom.sed
test ${DBG} -eq 1 && echo "fence 6"

if [ -s custom.sed ]
then
    more custom.sed
    echo -e "\t Hit return to continue ..." >&2
    read k <&2
else
    echo -e "\t Failed to create 'custom.sed'.  Unable to proceed!\n" >&2
    exit 1
fi

testout="Test_OUTPUT.cpp"

sed -f custom.sed "${testfile}" >"${testout}"
test ${DBG} -eq 1 && echo "fence 7"

if [ -s "${testout}" ]
then
    more "${testout}"
else
    echo -e "\t Failed to create '${testout}'.\n" >&2
    exit 1
fi

不幸的是，他们提出的似乎不起作用。 上面的执行日志如下：

fence 1
fence 2
fence 3
fence 4
fence 5
sed: file blockrep.sed line 19: unterminated `s' command
fence 6
     Failed to create 'custom.sed'.  Unable to proceed!

也许那里的专家可以解决导入的blockrep.sed脚本中的逻辑错误。 这将有广泛的应用，对包括 OP 和我在内的许多人都有好处。

Answer 3

这是一个以grep为中心的bash脚本解决方案（因为这些是 OP 明确提到的内容）：

Mac_3.2.57$cat replaceFunc.sh 
#!/bin/bash

# presumes code has been lint'd into consistent format 

oldFile=$1
newFile=$2

# find line # (oldFuncLineNum) of "void Component::initialize()" line
oldFuncLineNum=`cat $oldFile | grep -n '^void Component::initialize()$' | cut -c 1`

# find line # (oldSquiglyLineNum) of first "}" line after oldFuncLineNum
oldSquiglyLineNum=1
while [ $oldSquiglyLineNum -lt $oldFuncLineNum ]
do
  found=0
  while [ $found -eq 0 ]
  do
    oldSquiglyLineNum=`expr $oldSquiglyLineNum + 1`
    head -n $oldSquiglyLineNum $oldFile | tail -n 1 | grep '^}$' > /dev/null
    found=`test ! -f $? && echo "1" || echo "0"`
  done
done

oldTotSize=`sed -n '$=' $oldFile`
oldTailSize=`expr $oldTotSize - $oldSquiglyLineNum`

#echo "got: oldFuncLineNum = $oldFuncLineNum"
#echo "got: oldSquiglyLineNum = $oldSquiglyLineNum"
#echo "got oldTotSize = $oldTotSize"
#echo "oldTailSize = $oldTailSize"


# find line # (newFuncLineNum) of "void Component::initialize()" line
newFuncLineNum=`cat $newFile | grep -n '^void Component::initialize()$' | cut -c 1`

# find line # (newSquiglyLineNum) of first "}" line after newFuncLineNum
newSquiglyLineNum=1
while [ $newSquiglyLineNum -lt $newFuncLineNum ]
do
  found=0
  while [ $found -eq 0 ]
  do
    newSquiglyLineNum=`expr $newSquiglyLineNum + 1`
    head -n $newSquiglyLineNum $newFile | tail -n 1 | grep '^}$' > /dev/null
    found=`test ! -f $? && echo "1" || echo "0"`
  done
done

newDelta=`expr $newSquiglyLineNum - $newFuncLineNum`

#echo "got: newFuncLineNum = $newFuncLineNum"
#echo "got: newSquiglyLineNum = $newSquiglyLineNum"
#echo "got: newDelta = $newDelta"


# Display oldFile up to the function:
cat $oldFile | head -n $oldFuncLineNum

# ... followed by the new function:
cat $newFile | head -n $newSquiglyLineNum | tail -n $newDelta

# ... followed by the remaining portion of the oldFile:
cat $oldFile | tail -n $oldTailSize

exit 0
Mac_3.2.57$
Mac_3.2.57$
Mac_3.2.57$
Mac_3.2.57$cat File1.cpp 
blah blah
blah
void Component::initialize()
{
    my_component = new ComponentClass();
}
blab blab blab
...
Mac_3.2.57$
Mac_3.2.57$
Mac_3.2.57$
Mac_3.2.57$cat File2.cpp 
yaddy yadda
yaddy yadda
void Component::initialize()
{
    if (doInit)
    {
        my_component = new ComponentClass();
    }
    else
    {
        my_component.ptr = null;
    }
}
blah
blah
blab blab blab
...
Mac_3.2.57$
Mac_3.2.57$
Mac_3.2.57$
Mac_3.2.57$./replaceFunc.sh File1.cpp File2.cpp
blah blah
blah
void Component::initialize()
{
    if (doInit)
    {
        my_component = new ComponentClass();
    }
    else
    {
        my_component.ptr = null;
    }
}
blab blab blab
...
Mac_3.2.57$

Answer 4

回到我原来的非功能性答案（现已删除）的有效解决方案。

我设法解决了 linuxtopia 上发布的原始有缺陷的sed脚本的问题，并且能够获得我正在寻找的通用解决方案。 这是这里的答案。