Add spaces to page.extract_text() output concatination

[damasch]

If the method page.extract_text() is used.
The extracted text has no white spaces.

Actual output from the sample.pdf:

Text FormattingInline formattingHere, we demonstrate various types of inline text formatting and the use of embedded fonts.

There are missing whitespaces.

Text FormattingInline formattingHere, we demonstrate various types of inline text formatting and the use of embedded fonts.
               ^                ^

Expecting:

Text Formatting 
Inline formatting 
Here, we demonstrate various types of inline text formatting and the use of embedded fonts.

Or Minimum:

Expecting:

Text Formatting Inline formatting Here, we demonstrate various types of inline text formatting and the use of embedded fonts.

Environment

$ python -m platform
macOS-13.2.1-x86_64-i386-64bit

$ python -c "import pypdf;print(pypdf.__version__)"
3.0.1

Code + PDF

from PyPDF2 import PdfReader

reader = PdfReader("sample.pdf")

for page_num in range(len(reader.pages)):
      page = reader.pages[page_num]
      text = page.extract_text()

Sample

sample.pdf

Solution

In lines:

pypdf/pypdf/_page.py

Line 1658 in 23d81ff

output += text

pypdf/pypdf/_page.py

Line 1664 in 23d81ff

output += text

pypdf/pypdf/_page.py

Line 1696 in 23d81ff

output += text

pypdf/pypdf/_page.py

Line 1720 in 23d81ff

output += text # .translate(cmap)

pypdf/pypdf/_page.py

Line 1833 in 23d81ff

output += text

pypdf/pypdf/_page.py

Line 1854 in 23d81ff

output += text

pypdf/pypdf/_page.py

Line 1868 in 23d81ff

output += text # just in case of

There is a concatination without whitespaces.

output += text 

If you change the code into this:

output += " " + text 

The new output will be:

      Text Formatting   Inline formatting   Here, we demonstrate various types of inline text formatting and the use of    embedded fonts.

Maybe change the return value to:

pypdf/pypdf/_page.py

Line 1871 in 23d81ff

return output

return output.strip()

The text result will be:

Text Formatting   Inline formatting   Here, we demonstrate various types of inline text formatting and the use of    embedded fonts.

There are allready uneccessary whitespaces but better result as before.

[pubpub-zz]

the modification is not so simple because il will add extra space in numerous document. adding space criteria should rely on text width calculation.
for information ,a bench mark measures the quality of the text extraction
https://github.com/py-pdf/benchmarks

[pubpub-zz]

White space are adressed in issue #1507
I will add the test to group all the possible tests.

[pubpub-zz]

@MartinThoma
I propose to close this PR as not planned