heredoc seems to parse contents even with the quoted delimiter in shell prompt

[Hyunho Cho]

Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -g -O2
-fdebug-prefix-map=/build/bash-a6qmCk/bash-5.0=.
-fstack-protector-strong -Wformat -Werror=format-security -Wall
-Wno-parentheses -Wno-format-security
uname output: Linux EliteBook 5.4.0-42-generic #46-Ubuntu SMP Fri Jul
10 00:24:02 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu

Bash Version: 5.0
Patch Level: 17
Release Status: release

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if i use "test.sh" file for running shell script like this, there are
no error messages appear


bash$ cat test.sh
#!/bin/bash

cat << "EOF"
this is a test comment
$(info $(foo ${bar)))
EOF


bash$ ./test.sh                      # no error messages appear
this is a test comment
$(info $(foo ${bar)))

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if i use the same script in shell prompt then strange error messages appear


bash$ cat << "EOF"
this is a test comment
$(info $(foo ${bar)))
EOF
bash: command substitution: line 798: unexpected EOF while looking for
matching `}'
bash: command substitution: line 799: syntax error: unexpected end of file
bash: command substitution: line 798: unexpected EOF while looking for
matching `}'
bash: command substitution: line 799: syntax error: unexpected end of file
this is a test comment
$(info $(foo ${bar)))